THE ECONOMIC GEOLOGY AND POTENTIAL

 

                                               OF THE

 

                  LOWER DAVIS-DUNKIRK MINE

 

 

                                           T12N – R2W – S.3

                                          YAVAPAI COUNTY, ARIZONA

 

 

 

 

 

 

 

 

                                                                   BY

                                                      DON L. JENKINS

                                           Certified Professional Geologist

                                                        Mining Engineer

                                               

                                                             CPG #3341

                                                          ME # 1594874

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                                                     FEBRUARY 24, 2006

 

 

 

 

INTRODUCTION

 

            At the request of Mr. Jason Wharton, owner of the Lower Davis-Dunkirk Mine, the writer of this report undertook an evaluation of the economic geology and potential of the Lower Davis-Dunkirk Mine.  The property consists of patented mining claims; namely, the Azurite, New Era, Ni Wet Millsite Lode, Little Kid, Wren, and Jay Hawker.  The primary area of interest for this evaluation included the Azurite, Ni Wet, and New Era patented claims, comprising approximately 53 acres.  Some work, although limited, was done on the Little Kid patented lode. 

 

            To this end, the writer with assistance from Mr. Steve Lewis and Bonnie Miller, spent a portion of January and early February, 2006 on the property, conducting geologic mapping, sampling, surveying, and examining both surface and underground mine workings.  In addition, an examination of road cuts, talus, detrital, and soil was completed.  During this period a dozer was brought onto the property and all existing roads, within the property, were rehabilitated; additionally, an old exploration road trench was opened up and the host shear zone, exposed in the road cut, was mapped and sampled.

 

            Historical records for this portion of the Davis-Dunkirk Mine are limited; consequently, a historical review of the property was minimal and confined predominantly to general geology and brief mention of old workings.  No significant technical information such as underground or surface mapping and sampling is available.

However, some useful information on the mine area is contained in old reports by Dickman, 1906,  Henley,1926, Montonati, 1982, Department of Mineral Resources, 1982,  Zinkl,1983, and the Davis-Dunkirk Mines, Inc., late 1980’s.  In essence, the work undertaken by this writer was basically grass roots exploration within old workings.  It is unfortunate that credible record keeping was not kept during previous operations and work programs, but this is not uncommon and is a burden that new mine owners must assume.  A brief discussion of the above mentioned reports is summarized as follows:

 

R. N. Dickman, 1906:

 

            Dickman describes the entire Davis-Dunkirk Mine from the lowest level (No.1) to the uppermost workings of the No. 21 level on the Davis No.3 North patented claim.  In the New Era Shaft Dickman mentions the bottom of the shaft containing .5’ to 1.0’ of sulfide ore, showing a value of Gold @ .30 oz/ton, Silver @ 12.22 oz/ton, and Copper @ 2.99 %. He describes the No. 1 tunnel in increments with a tunnel length of 912’. It is apparent that additional development was done after Dickman examined this level, since an old longitudinal map shows the No. 1 Level at over 1700’ in length.  No description of the first 120’ is given.  From 120’ to 180’ no ore is reported.  At 180’ a 4’ wide section of ore is reported to value $36.86/ton at 1906 prices.  From 184’ to 316’, according to Dickman, no ore exists.  At approximately 327’ from the portal, ore of “significant value” starts and continues to the 650’ measurement…………from 440’ to the 490’ mark the vein was reported as very narrow but well defined and averaging $32.38/ton.  From 490’ to 650’ the vein is reported to average 2.0’ in width, and assay $14.84/ton.  From 650’ to 912’ no ore was found.

 

            Dickman describes the No.6 Tunnel as having reached a length of 410 feet on 7/5/06.  According to Dickman very little ore was found up to the 300’ mark, but from 300’to 370’ continuous ore was encountered with high values reported.  Samples taken within this zone show ore ranging from 0.5’ to 5.0’in width, and ranging from $7.18/ton to $86.10/ton.  Obviously, at current metal prices, the ore tenor would be many times greater…………approximately 28 times greater.

 

 

James H. Henley, 1925:

 

            The Henley report discusses the various workings of the Davis-Dunkirk Mine, but with little or no backup information available to this writer.  A brief discussion of the No.1 and No.6 tunnels indicated some ore reserves that may have been mined at a later date.  Henley mentions a block of ore around the shaft, connecting the No. 1 and No.6 levels.  It is suggested that 5000 tons of ore exist, having an average value of $11.32/ton.

In addition, Henley reported a block of ore near the end of the No. 6 level, totaling over 30,000 tons at an average of $8.95/ton.  Judging from an old longitudinal section (Figure 3) a portion of this block has been mined.  An additional ore block was reported by Henley at a point some 400’ back from the face of the No. 6 level.  It does not appear that this block of approximately 31,000 tons has been mined.

 

 

Frank J. Montonati, 1982:

 

            Very important and valuable work was initiated by Montonati, a mining engineer and mine contractor, in 1981, consisting of rehabilitation of the 1000 Level (No. 1 tunnel), and the completion of a crosscut level (902) south of and approximately 140 feet vertically below the No. 1 tunnel.  Montonati states that 220,000 tons of ore are indicated above the No. 1 level, with 80,000 tons proven.  He suggests that the gross value of this ore at 1982 metal prices would be over $100,000,000…………..quite a statement indeed.

Montonati recommended development of the ore blocks, extensive sampling, economic studies of the ore blocks as they are encountered and sampled, and metallurgical testing.

Montonati also indicated that intersections of the “vein system” were encountered in the 902 crosscut, “verifying the strength and continuity typified in previous work on the property…………………there is no known data to support this conclusion, although it may very well be true.  He also indicated that the vein material included good to excellent values in heavy sulfides.

 

 

 

 

 

 

Department of Mineral Resources:

 

            On April 14, 1982 a report was submitted by Ken Phillips and Richard Beard, field engineers for the Arizona Department of Mineral Resources, regarding underground exploration work being done by Frank Montonati at the Davis-Dunkirk Mine.  The report by Phillips and Beard indicated the following:

·        The property was being held under lease by the Great Southern Mining Co.

·        The No. 1 drift was being cleaned out and sampling completed

·        At the time of their visit 60’ of the No. 1 level had been cleaned out and progress was awaiting track;

·        A crosscut level on the northwest side of Slate Creek had been driven into the mountain a distance of 100’, and 120’ of drift on the vein to the northeast had been completed.

·        The vein was exposed in the back of the drift, varying from 0.5’ to 5.0’ in width, containing sulfide mineralization of quartz-pyrite, chalcopyrite, pyrargyrite, and galena.

·        Values reportedly ranged from .05 to 2.0 oz/ton Au, 0.4 to 17 oz/ton Ag. 2 to 8% Cu, 0 to 2% Pb, and 0 to 0.2% Zn

 

 

 

Andrew Zinkel, 1983:

 

            Mr Zinkl, a registered mining engineer, reported on the southern portion of the Davis-Dunkirk Mine, specifically the area examined by this writer.  Zinkl has provided perhaps the most accurate and comprehensive review of the Azurite, New Era, and Ni Wet Millsite Lode claims to date.  Zinkl’s comments are summarized as follows:

 

 

 

Davis-Dunkirk Mines, Inc, 1985 or later:

 

            A corporate report was issued in the late to middle 1980’s, reporting on the Davis-Dunkirk Mine in general. Pertinent statements regarding the southern portion of the property are as follows:

 

 

 

Although the above historical information is important, the backup data to justify the various statements is either not now available, or has been lost over the many years during which time the property has remained idle.  If historical records, in particular sample maps, geologic mapping, cross-sectional data, and other pertinent underground and surface data cannot be found, the Mine’s potential can only be determined by completing much if not all of what has been previously accomplished, in addition to a more extensive exploration program that is discussed herein under CONCLUSIONS AND RECOMMENDATIONS.

 

 

 

PROPERTY LOCATION AND ACCESS

 

            The Lower Davis-Dunkirk Property is located within the northern Bradshaw Mountains, Senator Mining District, specifically in section 3, of Township 12 North, Range 2 West.

            The property is accessed by traveling from Prescott on the Senator Road approximately 11 miles, and then turning onto the Tillie Starbuck and Davis-Dunkirk mine road for about 3 miles to the west.  Road access is overall very good, including 8 miles of paved road to just beyond the small community of Groom Creek, then 3 miles to the Tillie Starbuck Mine turnoff.  Access is very good except for a mile or so of rough 4x4 road before entering the Lower Davis-Dunkirk Mine area……………..the road within the Lower Davis-Dunkirk Mine has been recently rehabilitated.

 

            The property is situated at elevations ranging from 6000’ to about 6700’and is confined to a high mountain desert environment, consisting primarily of shrub oak, but with scatterings of prickly pear cactus, manzanita, and at the lower elevations and within the Slate Creek drainage, ponderosa pine, fir, and some spruce trees..  This area normally is covered with snow from late December to early April.  The property lies on the southwestern slopes of the Bradshaw Mountain Range, resulting in warmer temperatures and less snow than the adjacent higher elevations.  Access during the winter months can be restricted due to snow cover.

 

 

GENERAL GEOLOGY

 

            The local geology has been described as Precambrian-age intrusives that are associated with schist, gneiss, Precambrian sediments and volcanics.  The entire geologic package also includes younger intrusive dikes that crosscut the Precambrian package, and in many instances are directly associated with vein fissures and shear zones by occupying the open space created by zonal shearing.  Rock types in the area generally include granite, granodiorite, diorite, schist, gneiss, mylonite, and in general terms felsite.  The area in and around the property has experienced intense ground movement as evidenced by the extent of faulting and shearing throughout.  Most observed mineralization at the Lower Davis-Dunkirk Mine is directly associated with a fine grained and somewhat silicified diorite.

 

 

PROPERTY GEOLOGY AND MINERALIZATION

 

            Mineralization, within the Lower Davis-Dunkirk property, is hosted by a shear zone at a rock contact between granodiorite and diorite.  At some locations along the shear zone the granodiorite grades into granite or a felsic rock that may be in fact an aplite or aplitic granite.  The shear zone is a fault contact hosting the Davis-Dunkirk vein…………this type of fissure vein is common within the Hassayampa and Senator Mining Districts.  Shearing along the granodiorite-diorite contact has resulted in sericitic schist to mylonite within the footwall zone of the contact.  The walls along the shear zone are intensely altered due to hydrothermal activity, together with the intense shearing.   Alteration products, as a result, include silica, kaolinite, propylite, alunite, sericite, and minor chlorite.  Fine grained pyrite and minor chalcopyrite are also noted and contained generally within the footwall mylonitization.  The term mylonite is used herein to define in general terms the sheared and sericitized granite footwall that exhibits strong schistosity.

            Epigenetic metallization has resulted in ore grade mineralization at the Lower Davis-Dunkirk Mine……. a direct result from hydrothermal activity and most likely some metasomatic replacement.  Interaction between hydrothermal fluids and favorable wallrock has likely played a roll in the deposition of ore minerals, in addition to strictly fissure filling.  This is indicated by the presence of intense wallrock alteration and moderate sulfidization of the deposit.

 

            Fissure filling and alteration within the Davis-Dunkirk shear zone is variable and inconsistent.  The quartz vein occupying the shear zone is generally 0.5’ to as much as 10’ wide and undulates both along strike and dip.  Pinching and swelling of the fissure is common throughout the known strike length of the shear zone.  The vein generally lies along the footwall contact, but local crossover to the hangingwall is noted at some underground locations.  The total width of the shear zone varies from 15’ to as much as 50’in width.  The vein/shear zone system is intensely silicified, with the host rocks being

altered at contact to silca, kaolinite, propylite, and argillite…………these alteration products could be key indicators in continued exploration of the deposit.

 

            The spatial relationship of the Lower Davis-Dunkirk deposit is important and will guide future exploration and development.  This deposit trends N 50 E to N 60 E and dips from 65 to vertical.  Surface and underground mapping, together with careful review of previously developed longitudinal maps, clearly indicate the presence of ore shoots raking to the northeast at 45 to 60 degrees.  The successful search for and development of ore reserves will ultimately require a determination of dimensional shape and characteristics of ore shoots.  Accurate downward projection of ore shoots will depend on exploration results, and from surface and underground development.

 

            Recently completed mapping and sampling, together with a review of data contained in historical reports, clearly suggest that “hi-grade” mineralization is confined to ore shoots.  It is believed that the “hi-grade” ore contained in shoots is the result of structural controls.  Although underground and surface exposure is currently limited, evidence of structural ore control is indicated by north to northwest trending faults and shear zones, intersecting with the Davis-Dunkirk vein system.  It is noted that the known ore shoots start near structural loci, and most likely end in the same fashion.  It is not clear if these N-NW trending structures have created permeable conduits for ore fluid movement and are thus so-called “feeder veins”, or if the structural characteristics have provided dialation and changes in trend and dip of the shear zone, resulting in higher ore tenor within these zones.  It may very well be that both have collectively created favorable conditions for increased ore values.

 

            Mineralization within the Lower Davis-Dunkirk shear zone consists of the following:

 

·        Silica/quartz

·        Limonite

·        Goethite

·        Hematite

·        Chrysacolla

·        Malachite

·        Azurite

·        Pyrite

·        Chalcopyrite

·        Pyargyrite

·        Proustite

·        Polybasite

·        Native gold

·        Native silver

·        Manganese oxides

 

Previous history and recent sampling suggests that the primary metals of economic importance are gold, silver, and copper…….not necessarily in that order.  Most gold content found in the Lower Davis-Dunkirk vein deposit is associated with supergene enrichment within the near-surface oxide zone, and contained in quartz-limonite boxworks, sugar quartz, and especially with manganese coated vughy quartz.  However, it is also noted that apparent leaching of gold values may have occurred as a result of hi-level sulfidization at or near surface. The result is an erratic emplacement of supergene enriched gold mineralization. Gold is also prevalent in pyrite and chalcopyrite within the ore shoots, and will be found to be associated with the sulfide zone below the No. 6 level. Silver sulfosalts and native silver are present in the upper levels of the mine within the zone of oxidation; whereas, silver sulfides are found below in the transition and sulfide zones.   Copper values are spread throughout the shear zone system, as is evidenced by the presence of copper oxides in the oxide and transition zones, and the copper sulfide, chalcopyrite, found with pyrite in the sulfide zone.  Copper mineralization is not confined to the core vein or quartz fissure; conversely, copper metallization is noted throughout the entire shear zone………wall to wall.

 

As near as can be determined thus far, most economic values in gold, silver, and copper, are confined to “hi-grade” zones known as ore shoots.  Favorable metal prices, together with bulk mining methods, may allow for exploitation of most, if not all, of the shear zone at some point in time; otherwise, exploration and mine development will have to focus on the search for and exploitation of “hi-grade” zones; specifically, ore shoots, lenses, and pockets.

 

            A question that inevitably comes up is……………How deep will the ore go?  This is an important question that cannot always be answered; nevertheless, based on specific criteria, at least an educated guess can be achieved.  The answer lies in geologic evidence, or lack thereof, for structural or mineralogical “bottoming” of an ore shoot and/or deposit.  Locally, mines in the area have continued with depth, and operations have ceased due to insufficient metal prices, depth of operations, inability to effectively process gold-bearing sulfide ore, poor management, and other non-geologic controls.  The Lower Davis-Dunkirk mine exhibits mesothermal characteristics for mineral deposition……. with no known evidence for shallow mineralogical bottoming.  It is likely that this deposit will continue to considerable depth and far below current underground exposure.  The critical unknowns are structural implications.  The area has been subjected to ground movement as evidence by numerous intersecting faults and localized shearing; consequently, the potential for structural termination or dislocation of the deposit at depth, or portions thereof, should not be ignored in all phases of exploration and planning of potential mine development.  This fact alone is just one important reason for determining spatial characteristics of known ore shoots and conducting comprehensive geologic mapping.

 

            The Davis-Dunkirk ore deposit appears to be a relatively high sulfide system and controlled by structural features.  It is the structural patterns and intersecting loci that will be of great significance in developing potential ore reserves, whether for selective mining of ore shoots, or a bulk mining program.  Obviously, favorable metal prices and  metallurgical considerations, will also be major factors in future mine development.

 

 

RECENT WORK COMPLETED

 

            During a portion of the months of January and February exploration and evaluation efforts were conducted at the Lower Davis-Dunkirk mine.  This work consisted of first completing a control survey of the mine area, including accessible surface and underground workings, mine dumps, roads, exploration roads/trenches, and topographic features, and evaluating historical data.  Following this work, all accessible mine workings were geologically mapped in general terms, and rock and ore sampling completed.  Additionally, exploration reconnaissance of the claims was conducted to determine the presence of other mineralized structures, fault and shear zones, rock type, and location of old workings.  Rehabilitation of the existing mine road was completed to facilitate present and future exploration activities. 

 

 

ECONOMIC GEOLOGY AND POTENTIAL

 

            As previously stated herein, the Davis-Dunkirk Mine hosts a gold, silver, and copper-bearing shear zone deposit.  This deposit contains a quartz fissure vein that has been partially explored and developed over a period of roughly 100 years.  Most all past production has been confined to “hi-grade” zones, specifically ore shoots.  In the course of developing the ore shoots, considerable exposure has resulted of the host shear zone and lower grade portions of the fissure vein.  It is this exposure, together with previous development, that provides the foundation for evaluating the mine’s potential.  It is obvious from previous exploration efforts and evaluations that the Lower Davis-Dunkirk Mine has produced moderate quantities of ore, primarily from the “hi-grade” ore shoots, and that the potential for ore remaining in these shoots is high.  In addition, the old data and current exposures all suggest that the potential for a bulk mining program may be significant.  The shear zone is continuous throughout the property, but has been subjected to transecting and cross faulting, resulting in potential structural implications……..which may be favorable ……….or just the opposite.  Exploration activities will be required to determine the implications of structural features at the mine.

 

            The Lower Davis-Dunkirk shear zone deposit is actually synonymous with the Davis Vein, which is a southern split or branch of the Upper Davis-Dunkirk shear zone system.  A considerable distance north of the No.6 shaft and level the split is evidenced by workings northwest of the No.6 level, far up the mountainside, on a broad zone of alteration and shearing.  This zone, the Dunkirk Vein, is very broad and characteristically much lower in tenor than the Davis Vein.  Most past development in the local area has been on the Davis Vein.

 

            Potential economic mineralization is contained within two types of geologic targets.  First, and historically the most important one, is a quartz-filled fissure vein occupying a broad shear zone.  Within the quartz fissure are structurally controlled ore shoots, containing the “hi-grade” gold values that have been the subject of past operations.  A second target that can no longer be ignored is that of the entire shear zone itself.  This structure trends through the property in a NE direction for approximately 2300’, indicated by old workings and exposures both at surface and underground, and reconnaissance exploration. It is also evident that the shear zone has been exposed over a vertical depth of 500’ or more on the Lower Davis-Dunkirk Mine, and an additional 1000’ vertical feet to the top end of the Upper Davis-Dunkirk Mine, together with a lateral extension of some 3200’.  This certainly suggests both extensive lateral and vertical potential of the shear zone system.  In fact if one assumed an average width of 25’, a strike length of 5500’, a depth potential of 2000’, with 40% removed due to slope (topography) and previous mining, the total potential for mineralized material is then:

 

            (5500 x 2000 x 25) x 60%/12/ft/ton = 13.75 million tons

 

Of this amount, approximately 6 million tons could lie within the boundaries of the Lower Davis-Dunkirk Mine as a potential bulk mining target.  This is very speculative at this point but not unrealistic to consider as part of any exploration program.

 

            Recent sampling and mapping has been conducted to determine if adequate ore potential remains that would justify a comprehensive exploration program, and perhaps small scale development of “hi-grade” ore remaining within and adjacent to the old workings.  To this end, a program of surveying, sampling, mapping, and evaluation of existing data, was undertaken and completed in mid-February, 2006.  The program consisted of the following:

 

 

 

To take advantage of weather conditions, following completion of the control survey, surface sampling and mapping was first initiated since no snow groundcover was present.  Fortunately this was completed prior to the first snowfall that did occur the very first day of underground sampling; however, weather conditions quickly reverted back to the unusually dry and warm winter that the area had been experiencing.  All accessible underground workings were geologically mapped and sampled to the extent necessary to adequately evaluate the consistency of gold and silver values along the trend of the shear zone, and the ore tenor within accessible portions of old stopes.  To this end, 19 samples were cut in underground workings, 25 in surface workings, 17 were taken in conducting surface reconnaissance exploration, 13 from dumps, and 7 samples were cut in mill tailings.  The geologic mapping and sampling tends to confirm that “hi-grade” ores are confined to ore shoots as suggested in previous reports and one longitudinal map (Figure 3); in addition, it is clear from the sampling done both on surface and underground that ore of lower tenor, perhaps milling or leaching ore, exists throughout the entire shear zone, representing a potential bulk tonnage target.  The arithmetic average of all 81 samples is as follows:

 

 

 

Several aspects must be kept in mind when evaluating all samples taken.  First, many surface and underground samples were deliberately taken in the walls of the shear zone, in low-grade or non-mineralized rock, to specifically determine background information, and to define the limits of significant metal values in the walls of the shear zone; second, localized leaching of gold, silver, and copper at and near the surface has removed some metal values from specific zones.  The base metal nature of the Davis-Dunkirk shear zone has, during periods of erosion and deuteric alteration, created an acidic chemistry that has removed gold, silver, and copper from some portions of the deposit……….most likely re-depositing these metals deeper into the system; and third, the “hi-grade” ore tenor is localized in ore shoots, lenses, and pockets, none of which could be accessed to any significant degree for serious sampling and evaluation.  All samples are described in Appendix I , attached to this report.

 

Discussion of Samples:

 

  1. Surface Sampling

 

A review of the attached maps will show the location of all surface samples taken.  The surface sampling completed by this writer confirms that ore of “hi-grade” tenor does indeed exist at and near the surface within old workings.  It also shows that the “hi-grade” zones are controlled and localized within ore shoots.  Mapping and examination of the surface workings clearly shows where previous mining focused on ore shoots.  Additionally, sampling into the walls of the host shear zone suggests that significant values in gold, silver, and copper exist, justifying a careful look at the entire shear zone package for potential bulk mining.  The presence of “hi-grade” ore at the Lower Davis-Dunkirk Mine is shown in samples A-1, A-2, A-4, A-7, A-12, and A-25.  Sample A-1 was taken just outside from the middle level, just below the No. 6 adit, from large boulders of oxidized ore, containing considerable quartz, limonite/goethite veining, very vughy, and scattered veinlets of pyrite with chalcopyrite.  This sample yielded .362 oz/ton Au, and 8.20 oz/ton Ag.  Sample A-2 was taken from the same location as for that of A-1…….this sample contained far more sulfides.  Although gold assays just .042 oz/ton, values in silver and copper were encouraging, assaying 11.8 oz/ton Ag, and 5.18% Cu.

 

Sample A-4 is a chip channel taken from the northern portion of the workings above the No. 1 level.  A channel across 9.0’ of sheared and silicified mylonite was cut within the left rib of the entrance to an open stope.  The significance of this sample lies in the fact that the material sampled is outside the main fissure or vein.  Clearly, this material must be evaluated in any future exploration program.  The entire 9.0’ averages 0.541 oz/ton Au, and 39.65 oz/ton Ag.  Since this material lies in the footwall underneath the quartz portion of the ore shoot, it must be assumed that previous mining may have ignored footwall extensions of what is at today’s metal prices economically viable ore.  To accentuate the point, the in-ground gross value of this 9.0’ interval, outside the main vein, is as follows:

 

            Gold @ $560/oz………….Silver @ $10/oz

 

            Value = (.541 x 560) + (39.65 x 10) = $693.61 per ton

 

Based on this analysis, potential footwall extensions from known ores shoots, as well as newly discovered ones, must be carefully tested and fully evaluated.

 

Sample A-7 was taken in the surface workings above the No.1 level, and near the northern end of the workings at the face of an open stope. This sample certainly confirms the presence of “hi-grade” ore confined to an ore shoot.  The sample was taken as a panel sample across the entire exposed face some 6’ in width, assaying 0.925 oz/ton Au, 11.40 oz/ton Ag, and 0.113 % Cu  (most copper has been leached).

 

Sample A-12 was extracted near the end of the surface road trench from scattered boulders of vughy quartz, stained with iron oxides, and what appears to be manganese oxides……this sample assays 0.315 oz/ton Au, and 14.35 oz/ton Ag.

 

Sample A-25 was taken as a select representation of what visually appears to be “hi-grade” gold/silver ore.  Select chips were extracted from numerous and scattered ore-bearing rock from the surface workings above the No.1 Level. The assay results proves this theory accurate, as this representative “look” at suspected “hi-grade” ore assayed 1.091 oz/ton Au, and 17.40 oz/ton Ag.  Based on this sample, a significant tonnage of “hi-grade” ore is available at surface in and around the old workings.

 

Other surface samples of significance include those taken in the walls of the shear zone, road cut samples of the shear zone taken just above the No. 6 tunnel, and samples from several “zones” of mineralization found in float and detrital. Sample A-6 is a good example of footwall mylonite containing significant values far outside of any known ore shoot.  This sample, across 25’ of altered and silicified mylonite, yielded an assay of 0.061 oz/ton Au, and 0.75 oz/ton Ag.  The potential in gold alone is worth considering from the standpoint of underground and/or surface bulk mining.  A sample taken approximately 550’ south of the No. 1 Level, along the trend of the shear zone, shows vughy quartz/limonite and oxidized mylonite over a width of 25 to 30’, primarily within float and detrital material, although some physical exposure was found.  The sample is significant in that a southerly extension of the shear zone is now confirmed, and that gold and silver tenor, although low, does suggest the need for an exploration program to the south of current workings.  Very old workings, now healed and covered with brush, were found about 600’ south of this sample.  Unfortunately, very little in-place mineralization could be found to sample………primarily due to heavy soil and brush cover.

 

Road cut samples A-26 through A-30 yielded disappointing results.  Very little gold or silver was detected; yet, less than 75’ directly below and within the No. 6 level, very significant gold and silver ore tenor is evident.  It is believed that surface leaching and oxidation has removed most of the precious metal values from this exposure………the exposure will have to be cut deep enough to expose, for sampling, material that has not been altered from the affects of deuteric alteration and chemical attack.

 

Another sample of interest is A-14, taken directly at the footwall contact near the face entrance to the No.6 adit.  As in surface workings above the No.1 level, a broad zone of silicified and oxidize mylonite is present at or near the footwall contact.  A panel sample taken across 8’ of this material assays 0.125 oz/ton Au, and virtually no silver……….more evidence that the footwall of the Davis-Dunkirk shear zone hosts significant value in gold, and has been ignored up to the present time as a potential source of gold ore.

 

 

  1. Underground Sampling

 

Samples taken from underground workings were limited in scope and extent due to restricted access.  Although the No. 1 and No. 6 levels show extensive underground development, based on old maps, caving and filling from existing stopes have for many years prevented safe access. Samples were cut from the entrance to the No 1 level in a distance of about 120’, from which a total of 11 samples were removed.  The sampling overall was disappointing but not unexpected since nearly all sampling had to be completed outside of the known ore shoot……..due to access.  Of significance, all samples did show some gold and silver value; one taken from near the entrance to the first observed stope, assays 0.212 oz/ton Au, 2.95 oz/ton Ag, and 1.8% Cu. A number of other samples taken from the entire shear zone, along the back of the drift,  shows ore tenor in excess of .04 oz/ton Au, nearly 2 oz/ton Ag, and about a 1/3 % in Cu.  It is apparent that additional in-fill sampling is needed, in addition to gaining access to the old stopes for detailed sampling of ore that is contained in both the main fissure vein, and any footwall extensions where exposed.

 

The short drift just below the No.6 level provided some samples of significance and interest.  For example, sample A-21 was taken from the face of what appears to be a connecting stope from below.  This sample of 4.5’ of width is composed of a dense “chocolate” looking goethite/limonite in silicified mylonite.  The quartz within the zone is very vughy and appeared at the time of sampling to reflect potential “hi-grade”. It is definitely not of “hi-grade” ore tenor but nonetheless is ore with a respectable grade of 0.174 oz/ton Au, and 2.55 oz/ton Ag.  Nearby, in the right rib of the entrance to this short level, a 5’ panel sample was cut across a brownish colored and oxidized mylonitic aplite-granite.  To this writers’ surprise, the material assays .088 oz/ton Au, .05 oz/ton Ag, and 1.39% Cu (A-22).  Beyond sample A-21, a sample was cut across the face of exposed vein material, over a distance of 3.5’, averaging .096 oz/ton Au, 9.3 oz/ton Ag, and an impressive 3.12% Cu. It is evident that leaching of silver in particular, and to some extent gold and copper, has occurred within this zone.  This area conforms with those descriptions provided by previous investigations, indicating an ore shoot of unknown dimension exists in the area of the No.6 shaft, connecting the No. 1 and No. 6 levels.

 

The entrance to the No.6 drift provides some sampling opportunity; unfortunately, a short distance from the adit entrance, the level is completely blocked by caving.  Samples taken at this level include A-14 through A-20.  Overall ore tenor was very low but expected since the entrance to the No. 6 Level is outside of any known ore shoot.  Sample A-14, discussed above, did show at the footwall contact approximately 8’ of silicified gold-bearing mylonite, assaying .125 oz/ton Au…………..this sample is very important in that it confirms other sampling on the property, indicating significant gold values are contained within the footwall portions of the Lower Davis-Dunkirk shear zone.  In fact sample A-22, taken in the adit entrance below the No.6 Level, shows, as discussed above, some 5’ or more of mineralized hangingwall, containing a very significant quantity of gold.  Hence, the hangingwall portion of the shear zone may at specific locations provide additional targets for the development of potential ore reserves. 

 

 

  1. Reconnaissance Sampling

 

Although of limited extent, some old workings on other vein/fault zones, together with mineralized float on the Davis-Dunkirk shear zone trend, were found and sampled.  Heavy brush cover made reconnaissance exploration very difficult; nevertheless, several old workings, as shown on the enclosed maps, were encountered, indicating that mining in the area was not confined exclusively to the Davis-Dunkirk shear zone.  On the northern end of the Ni Wet Millsite Lode, and the southern edge of the Little Kid patented claim, three prominent vein structures were found as evidenced by dumps and inaccessible underground workings.  The northernmost structure consists of approximately 8’ of crushed and intensely silicified diorite.  The vein in fact may actually be a remobilized diorite dike.  The trend is to the north and on an intersecting course with the Davis-Dunkirk shear zone.  Sample A-51 was taken across the zone, assaying .004 oz/ton Au, 1.10 oz/ton Ag, and .108% Cu.  A dump in the order of 3000 to 5000 tons lies below a caved adit.  Obviously, additional sampling is necessary to  evaluate this structure.

 

A distance of about 210’ to the south of sample A-51 lies a small dump of about 1000 tons.  Just above the dump a partially caved adit shows a minimum of 6’ of vein quartz, crushed diorite, and heavy oxides of limonite and goethite.  The vein structure seems to parallel the vein exposed at sample A-51.  Both structures dip steeply to the south at approximately 70 degrees.  At this location sample A-52 was taken of representative vein material, assaying .017 oz/ton Au, 0.35 oz/ton Ag, and only minimal copper.  About 140’ further south of sample A-52 lies another vein structure of roughly 2.0’ in width.  This fault zone trends N 50 E and dips steeply to the west at 85 degrees.  The fault zone is quartz filled, consisting of sheared and silicified diorite on both footwall and hangingwall.  A small shaft was sunk on this structure, resulting in approximately 500 tons of dump material.  Sample A-53 was taken across the exposed vein near the edge of the shaft, yielding .187 oz/ton Au, and only minor silver.  The dump adjacent to the shaft was sampled, as reflected by sample A-54, assaying .004 oz/ton Au, and 0.65 oz/ton Ag.  All three of these structures warrant further investigation.

 

Sampling of mineralized exposures in the mine road traversing the property shows no precious metals of significance.

 

Two samples taken from the southern end of the property show the continuation of the shear zone for at least 1000 feet south of the No. 1 adit.  This fact is also verified by the 902 crosscut which intersects the shear zone about 100’ from its’ portal, and approximately 420’ southwest of the No. adit.  Figure 5 shows the relationship of the shear zone trend and sample locations.  Sample A-61 was taken approximately 1100’ south of the No.1 adit from float and detrital material spread over a distance of about 40’.  The material sampled consists primarily of silicified mylonite, vughy quartz, and a high percentage of limonite.  Although this sample shows only trace amounts of gold and silver, it is obvious that the Davis-Dunkirk shear zone continues to this point, and appears quite wide.  Further evidence of continuation of the shear zone is provided by sample A-62.  Taken approximately 550’ south of the No.1 portal, on top of the ridge, this sample was cut over 30’ of altered and silicified mylonite, containing vughy quartz, boxwork limonite, and some manganese staining.  This sample assays .04 oz/ton Au, and 1.00 oz/ton Ag.   These samples are quite significant considering the affects of surface leaching and deuteric alteration..  The 902 crosscut intersects the shear zone about 420’ south of the No.1 portal, and 140’ below in elevation, confirming a continuation of a southern trend of the shear zone.  A representative sample of the vein material from the dump outside the portal of the 902 crosscut yielded an assay of .028 oz/ton Au, 3.85 oz/ton Ag, and 2.90% Cu.  In addition, a report by the Arizona Department of Mineral Resources in 1982 describes work being completed at the 902 crosscut.  The mineralization being removed from the effort was described as sulfides assaying from .05 to 2.0 oz/ton Au, .4 to 17 oz/ton Ag, 2 to 8% Cu, and significant values in lead and zinc. The collective information derived from sampling and exposure of the southernmost portion of the Davis-Dunkirk shear zone, south of the No.1 portal, indicates that a continuance of exploration in this area is well justified.

 

 

 

  1. Sampling of Mine Dumps

 

A total of 13 samples were extracted from various mine dumps throughout the property.  Figure 13 shows the location of dumps and respective samples.  All samples were taken after hand excavated holes were dug.  The sample results  suggest that significant values in gold and silver may be present for economic consideration. At some point, a backhoe will be required to excavate holes deep into the dumps to expose for sampling all layers from top to bottom.  Only then will an accurate reflection of dump tenor be achieved.  Nevertheless, some hand samples taken from the dumps, show economically viable values.   As such, there is undoubtedly some portions of the dumps that could be easily determined as ore reserves by a more detailed sampling program.  Justification for such a program lies in the volume of the dumps, together with the limited sampling results…..a summary analysis is offered as follows:

 

 

Dump outside the No.6 portal……….waste dump (no values)

 

 

Dumps outside of the No.6 shaft:

(a)        2000 to 4000 tons…….assays from .001 to .101 oz/ton Au, .05 to 3.90   oz/ton Ag;

(b)        500 to 1000 tons with one sample @ .164 oz/ton Au, .05 oz/ton Ag

 

 

Dump outside of No. 1 Level:   500 to 1000 tons with assays ranging from .043 to .078 oz/ton Au, and .05 to 3.05 oz/ton Ag;

 

Dump out from 902 Crosscut:    1000 to 2000 tons:  Two samples at .028 and .001 oz/ton Au, 3.85 and .05 oz/ton Ag, and one Cu assay at 2.90 %;

 

Dump out from reconnaissance sample A-51:  dump contains approximately 3000 to 5000 tons………..no assays

 

Dump out from reconnaissance sample A-52:  dump contains approximately 1000 tons……….one sample @ .017 oz/ton Au, .35 oz/ton Ag;

 

Dump out from reconnaissance sample A-53:  dump contains approximately 500 tons……….dump sample A-54 shows .004 oz/ton Au, and .65 oz/ton Ag.

 

Small dump out from No. 6 adit:  dump contains about 50 tons averaging .10 oz/ton Au, and 1.05 oz/ton Ag.

 

 

 

  1. Sampling of Mill Tailings

 

A total of 7 samples were cut from the various piles of mill tailings that are located at the southern end of the property.  Samples were cut across exposed layers of the tailings and should accurately represent contained gold and silver content.  It would be advised to cut sample sites into the tailings piles with a backhoe before further consideration of any attempt to extract precious metal values.  The total tonnage of the tailings is not known and should at some point be surveyed and measured.  A visual estimate of the volume is approximately 20,000 tons.  Mill tailings samples are listed as follows:

 

T-1:      .021 oz/ton Au, .05 oz/ton Ag

T-2:      .007 oz/ton Au, .95 oz/ton Ag

T-4:      .005 oz/ton Au, .70 oz/ton Ag

T-5:      .021 oz/ton Au, 1.7 oz/ton Ag

T-6:      .004 oz/ton Au, .80 oz/ton Ag

T-7:      .004 oz/ton Au, .80 oz/ton Ag

T-13:    .010 oz/ton Au, 1.50 oz/ton Ag

 

Significant values in the mill tailings do indeed exist; however, a more thorough sampling program should be completed prior to considering any processing of the mill tailings.

 

 

ORE POTENTIAL:

 

Historically it is obvious through past reports and other data that the ore potential of interest at the Lower Davis-Dunkirk Mine has been “hi-grade” gold – silver ore confined to ore shoots. This type of potential is without question still important and remains as the primary target for developing a profitable mining operation.  A second target of perhaps equal importance is the entire shear zone itself as a bulk tonnage deposit.  Recent sampling indicates that gold and silver values in particular, and perhaps copper beneath the zone of oxidation, are present in significant quantity within the footwall portion of the shear zone, and directly beneath ore shoots.  It is also possible that the entire shear zone between ore shoots may merit an exploration program by means of drilling and selective surface trenching.

 

Proven ore reserves within Lower Davis-Dunkirk shear zone are minimal at the present time and difficult to formualte an average value for such reserve; however, the potential for developing ore reserves of merit is high.  A brief discussion of ore reserves in all categories is summarized below:

 

[Proven Ore Reserves]

 

1.                  The dumps represent a proven tonnage of milling grade material that most likely could be processed along with mine feed.  The only dumps that can be considered proved with significant value include the two dumps outside from the No. 6 shaft, and the dump near the No. 1 portal.  The largest dump of approximately 3000 tons seemingly will average about .031 oz/ton Au, and 1.13 oz/ton Ag…….copper is unknown.  The second and smaller dump contains approximately 600 tons of material averaging .164 oz/ton Au, and no significant silver.  The calculated in-place gross value of this reserve is:

 

            (3000 x .031) x $560/oz + (3000 x 1.13) x $10/oz = $85,980.00

            (600 x .164) x $560/oz = $55,104.00                                                            

           

            Total Value of Dumps outside of No.6 Shaft:  $141,084.00

 

 

2.                  The dump out from the No.1 adit is difficult to measure since it may include part of the road/pad.  This possibility was ignored and the dump measured at approximately 750 tons averaging .065 oz/ton Au, and 1.73 oz/ton Ag.  The calculated in-place gross ore reserve value is:

 

            (750 x .065) x $560/oz + (750 x 1.73) x $10/oz = $40,275.00

 

 

3.         Mill tailings can be considered as a proven resource but detailed            measurements and more thorough sampling will be necessary to make a     precise valuation.  A preliminary examination provides an estimate of             roughly 20,000 tons, averaging 0.01 oz/ton Au, and 0.93 oz/ton            Ag………Cu is unknown.  The gross value of mill tailings          would   approximate the following:

 

            (20,000 x .01) x 560 + (20,000 x .93) x $10 = $298,000.00

 

            The mill tailings perhaps could be processed along with mill feed from a                         potential mine/mill operation.  The mill tailings do not appear to be             economically viable to support a stand alone processing operation.  The             value per ton is a mere $14.90.  It may be possible to make a profit by leaching the tailings provided an inexpensive startup operation was implemented.    Processing the tailings as part of a mine/mill operation will    most likely provide the more cost effective means of extracting precious             metals   from the mill tailings.  It is also of critical importance to define the       metallurgical efficiency of extracting the silver values.  If silver cannot     be effectively extracted, the mill tailings will not exhibit economic            viability.  Finally, any renewed mill tailings sampling program should    evaluate copper content.          

 

 

4.         There are no known in-place proven ore reserves at the Lower Davis-  Dunkirk Mine, other than what has been discussed above.  There are,         nonetheless, strong indications that considerable ore remains within the             shear zone itself and those ore shoots contained therein. This subject is discussed below under “Possible and Geologic Resources”.

 

 

 

[Possible & Geologic Resources]

 

            An evaluation of historical information, together with the most recent mapping and sampling program, indicates that ore reserves, based on current metal prices, do likely exist at the Lower Davis-Dunkirk Mine.  This is evidenced by a careful review of underground maps and selective sampling of “zones” previously ignored during past operations, together with the consideration of a bulk mining program versus a strictly underground “hi-grading” program from ore shoots, lenses, streaks, and pockets……….characteristically implemented in the past.  As precious and base metal prices strengthen, so does the potential for a bulk mining program at this property.  To exemplify this, the following details are offered:

 

·        An examination of underground maps clearly shows the spatial characteristics of known ore shoots.  Based on previous stoping information, together with the estimated size and configuration of such, it is concluded that the ore shoots are at a minimum of 300’ in length perpendicular to the ore shoots’ rake, or about 500’ in length along the drifts where the ore shoots are cut and exposed.  It is not unrealistic to assume that considerable ore remains in the old stopes, that several thousand tons of ore may be present around and above the stopes, and that an ore reserve of significant to large volume could exist below the known ore shoots.  Geologically it is likely that the known ore shoots continue down dip below current workings.  This ore will, however, most likely be sulfide in mineral content.  Evidence clearly exists that a considerable thickness of footwall ore in mylonite could be present geologically beneath the ore shoots, resulting in the potential for developing a considerable ore reserve amenable to bulk mining methods.

·        Although limited in extent, broad sampling into the footwall of the shear zone at different locations, exhibits encouraging results.  As previously mentioned herein, gold and silver metal content is very significant over considerable width within the mylonitic footwall of the Davis-Dunkirk shear zone.  Near the top of the stope exposed at surface above the No.1 level, roughly 30’ or more of highly mineralized mylonite is exposed.  One sample assays 0.54 oz/ton Au, and 39.65 oz/ton Ag, over a sample length of 9’.  Geologically above this sample, 8’ shows minor gold but 49.0 oz/ton Ag.  Essentially, a section of 17’ of exposed footwall averages about .27 oz/ton Au, and 44.3 oz/ton Ag, yielding an ore value of  $594.20/ton at current metal prices.  A short distance downhill from the above two samples a 30’ panel sample was taken around the nose of footwall exposure, consisting of intensely silicified and oxidized mylonite.  The assay from sample A-6 at this location shows this zone to average .061 oz/ton Au, and 0.75 oz/ton Ag. This 30’ appears to be geologically beneath the above two samples, indicating even more mineralized width in the footwall.  Intersecting cross faults appear to have created a permeable zone of crushing, silicification, and subsequent mineralization.  It is not clear at this time how extensive along strike or down dip this zone may be.  Additional evidence of mineralized gold and silver-bearing footwall mylonite lies at the entrance to the short adit adjacent to the No.6 shaft, and at the entrance to the No.6 level.  At both locations considerable mineralized footwall mylonite is exposed, and at the lower adit near the No.6 shaft, additional mineralized mylonite into the footwall is indicated but not accessible for sampling.  These two locations do not appear to be positioned within any known ore shoot; yet, significant gold value is indicated. For example, mineralized mylonite, at the footwall contact near the entrance to the No.6 level, yielded an assay across 8’ of .125 oz/ton Au, and minor Ag.

·        The recent mapping and sampling program is not extensive or specific to known precious metal potential and ore shoot location; nonetheless, this work does indicate that the Davis-Dunkirk shear zone contains appreciable gold-silver-copper content, and may host ore reserves in and around old stopes. It also suggests that a new target concept for bulk mining should be considered.  This overall effort has inherently generated conclusions and recommendations as set forth below.

 

 

 

CONCLUSIONS AND RECOMMENDATIONS:

 

The following conclusions are offered:

 

(1)   In the past, mining at the Lower Davis-Dunkirk property has been confined to “hi-grade” gold/silver ore contained within so called ore shoots, leaving “low-grade” ore for the time period behind.

 

(2)   “Hi-grade”ore likely remains in and around old stopes, up rake and down the rake of known ore shoots.  Considerable potential is suggested down rake below current workings and will in all likelihood be predominantly of sulfide content.

 

 

(3)   Sampling, mapping, and visual examination of accessible workings indicate the presence of mineable “hi-grade” ore at and near the surface above the No. 1 level.  Some accessible ore is also indicated within the short drift adjacent to the No. 6 shaft.

 

(4)   Examination of old records and accessible workings show spatial characteristics of the ore shoots, which can be effectively utilized in the planning of exploration and development programs.

 

 

(5)   The Davis-Dunkirk shear zone extends throughout the property, over a strike length of approximately 2300’.  This conclusion is based on sampling, mapping, and reconnaissance exploration conducted throughout the property.

 

(6)   The Davis-Dunkirk shear zone is a broad structural feature, hosting known “hi-grade” ore shoots, together with potential bulk tonnage targets, primarily in the footwall zones of the ore shoots, but potentially throughout much if not most of the shear zone trend.  The shear zone measures up to 50’ in width or more as evidenced by surface sampling and mapping.

 

(7)   The ore shoots at this property are structurally controlled by transecting faults………..possibly some chemical interaction within the walls of the shear zone has occurred.

 

(8)   The Lower Davis-Dunkirk shear zone represents a potential bulk mining target of 6 million tons or more, depending upon the depth potential of the deposit.

 

(9)   Localized bulk mining targets are present geologically/structurally beneath the “hi-grade” ore shoots.  The entire geologic/structural mineralized package could represent favorable targets for a potential localized bulk mining program, containing several hundred thousand tons per ore shoot.  For example, an ore shoot of bulk mining potential, measuring 40’ thick, 300’ of strike, and 1000’ of depth could yield 1,000,000 tons just from this one stope alone.  The ore shoot near the end of the No. 6 level is such a possibility.  The entire shear zone trend could yield much greater volumes but most likely of lower grade milling ore.  This is all speculative at this point but the technical data points toward a favorable potential yield.

 

(10)Reconnaissance sampling, mapping, and visual examination suggest that             other possibilities remain throughout the property.  Old workings to the          south of the No. 6 level, down in Slate Creek Canyon, show evidence of             previous exploration and development within mineralized and potentially             transecting fault zones. The size and content of three dumps, located out           from three totally separate mineralized structures, provide the evidence of of past underground development…….the volume of ore extracted and       processed is unknown.  More sampling and mapping of these mineralized          zones is warranted.

 

(11)Although known or proven ore reserves are at this time very limited, the            potential for finding and developing ore reserves of economic viability at       the Lower Davis-Dunkirk property is very high.  The evidence for such is             clear, and limited additional mapping and sampling will perhaps enhance             the possibilities.  As such, the Lower Davis-Dunkirk Mine is one of                   exceptional merit, likely hosting “a significant quantity of “hi-grade”      gold, silver, and copper ores, but perhaps more importantly hosting a       potential yet undeveloped shear zone bulk tonnage deposit.  Only time and        a concerted effort will determine the extent of ore reserves at this property.

           

           

 

     

 

 

 

 

            Recommendations for Exploration & Development:

 

(1)               Additional “in-fill” sampling should be completed within the surface workings located above the No.1 level.  In addition more detailed mapping in the form and style of detailed mine mapping should be considered within these workings to isolate “hi-grade” ore.

 

(2)                The stope within the No.1 level should be accessed…..this will require  underground rehabilitation.  A portion of this was apparently completed by Montonati in 1981-82.  A small to medium-sized LHD rubber tired unit should allow effective removal of fill and cave-in from the stoping areas, and beyond to the No.6 shaft intersection.  Scaling and some timbering may be required. The stope (s) should be accessed and thoroughly mapped and sampled to determine the extent of remaining ore, average tenor, and where exposed the mylonitic footwall examined and systematically sampled.  The data would also be effectively utilized to accurately position potential drill sites.

 

(3)               Re-opening the No.6 level may be very expensive and difficult; nevertheless, the entrance (adit) should be cleaned out and the drift opened up past the first caved area just to determine if open drift lies behind. A second examination of the No.6 portal did allow entrance into a partially caved stope that appears to actually be the continuation of the drift.  No attempt was made to go beyond this point but the degree of caving looked to be minimal.  If the No.6 level cannot be re-opened without a high cost, and safely, the ore shoot near the end of the level, together with ground between the No.6 shaft and the stope, can be tested by a comprehensive drilling program from the existing road and a proposed new road segment.

 

(4)               The entrance to the 902 crosscut requires removal of debris and proper drainage created.  This will allow access to the shear zone intersection and perhaps facilitate a sampling and mapping program.  Sample A-46 represents material extracted from the shear zone intersection, together with sampling reported by Montonati and the Arizona Department of Mineral Resources.  The results warrant rehabilitation of the crosscut and evaluation of this underground exposure.

 

(5)               Exploration roads are recommended to gain access to surface workings, to cut and test surface mineralization along the trend of the shear zone, to develop drill sites, and to gain access to dumps and tailings.   Figure 14 shows the approximate location of proposed road construction for surface exploration and drill site location.  Segment A, as depicted on the map, is a short stretch of road that will allow trenching across surface mineralization that is exposed in talus and float.  If excavated slightly further than shown on the map, a shallow drill site would result.  Segment B is an important effort since it will result in several surface exposures of the extension of the shear zone between the No.6 shaft and the workings above the No. 1 level.  The road would be split into two segments, the upper split dissecting the shear zone in two road locations and one hilltop location.  The lower segment would cut the shear zone near the northern edge of the existing stope.  This road spur would assist in evaluating the potential for “hi-grade” ore, as well as exposing the footwall mylonite.  “Hi-grade” oxidized ore could be removed from this road location.  The road segments would provide drill sites for shallow testing and blocking of ore reserves.  Segment C is a continuation of the surface road/trench just south of the No.1 adit.  The proposed road will access surface showings and allow for much needed trenching to gain exposure of the shear zone within an area where no exploration or mining has been attempted. Shallow drilling would be possible from this location.  Segment D gains access to mineralization near the far south end of the property, access to a portion if not all of the mill tailings, access to old surface and/or underground workings, and access for a potential home/cabin site.  Drilling would be facilitated from this road.  Segment E would be an important development for several reasons; first, deep level drilling of the shear zone could be completed; secondly, exposing the three silicified fault zones by trenching would be possible. Gaining access to the portals of the two workings would allow for opening and rehabilitation.  Access to the dumps would add to the property’s total ore resource.

 

(6)               The ore shoot near the end of the No.6 level should be projected and plotted on a topographic map.  The existing road will require surveying to the end of the property to tie in with the stope location, and accurately position drill sites that will dissect the ore shoot below the No.6 and No.1 levels.

 

(7)               Plotting the location of the stope situated within the No.1 level on a topographic map will allow for accurate positioning of drill sites intended to dissect and test the ore shoot below this level.  The drill sites should then be accurately surveyed and marked on the road for future reference.  A 3-D map of the shear zone with topography, road location, etc. should be considered for planning, geologic modeling, and ore reserve analysis.

 

(8)               All exploration roads should be accurately surveyed, mineralization exposed by trenching, geology mapped and plotted, and a sampling effort completed.

 

(9)               Geophysical prospecting methods may be considered to define the  position and intensity of sulfide mineralization below the current levels of exposure.  This may assist in determining the most effective location for drilling.  An induced polarization-resistivity dipole survey may be an effective tool in outlining the sulfide ore zones.  Other methods could be considered as well through consultation with an experienced geophysical engineer, having considerable experience in prospecting vein/shear zone deposits.

 

(10)           During the course of conducting the exploration program as outlined above, it is important that the search for “hi-grade” ore be a focus of the effort, and that the results be carefully plotted on surface and underground maps.  All data from future exploration efforts should to be catalogued, evaluated, and plotted on available maps.  An accurate and detailed compilation of exploration data is essential to properly and effectively evaluating the potential of the Lower Davis-Dunkirk Mine.

 

(11)           At some point it will be necessary to initiate metallurgical testing of the representative ores that may undergo development.  Such ores will include “hi-grade” oxide material, sulfide ore, transition ore, and ore representing the mineralized mylonite as a bulk tonnage target.

 

(12)           Upon completion of a comprehensive exploration program the collective data should be “translated” into proven, probable, and indicated ore reserves.

 

(13)           Accessing the known ore shoots, and/or bulk tonnage targets, below the No.1 level may be more efficient and cost effective from one or more crosscuts excavated from the east slope of Slate Creek Canyon.  The shear zone is dipping back towards the canyon floor; consequently, the dip of the shear zone will be sloping towards the entrance of a proposed crosscut from Slate Creek Canyon.  This decreases the distance that would be required to intersect with the downward projection of the shear zone.  Crossectional maps of the shear zone with topography will provide the necessary information to determine if this concept is advantageous for planning future development of ore reserves. 

 

 

 

Don L. Jenkins