Kimberly Gold Mine

Overview | Exploration | District Geology | Project History | Project Details

The Company is rehabilitating and exploring this former Idaho producer in pursuit of establishing mineral reserves and renewing gold production.

Project Overview
The Kimberly Gold Mine Project consists of 25 unpatented mining claims covering an area of known mineralization and favorable geology in the Marshall Mountain Mining District of central Idaho, roughly 20 miles east of Riggins. The property includes several buildings, mining equipment, a 100-ton per day mill, and nearly two miles of mine workings. Kimberly is rebuilding the project infrastructure, while exploring for additional mineralization, with the ultimate goal of returning the mine to production.

Exploration
Accomplishments to date at the Kimberly Gold Mine include:

Preliminary structural geological mapping studies, [maps: tunnels , veins] both from surface and underground, greatly enhancing knowledge of the geology and structural controls. Results include the discovery of an additional mineralized vein as well as two skarn horizons, potentially providing the first bulk tonnage drill targets for the project.
A bulk sampling study showing high-grade gold in both quartz and fault gouge in the Hickson-Bishop Vein (indicating local faulting occurred post-mineralization) and subsequent metallurgical work confirmed the need to incorporate both gravity and floatation circuits to achieve optimal mineral recoveries. Past production data has shown recoveries consistently above 90 percent without cyanide leaching.
The completion of 1,560 feet of the planned 10,000-foot drill program. The objective of the initial drilling was to intersect the Gold Crest Vein above and below the Gold Crest No. 2 Adit/Tunnel. However, although several mineralized structures and quartz veins were encountered, no significant gold intercepts were recorded and results are thus far inconclusive. Most of the historic workings at Kimberly are open both along strike and to depth and the potential to expand the current resource base is excellent.

The exploration program will include the continued rehabilitation of mine workings, additional surface and underground sampling of accessible veins, additional bulk sampling, the completion of surface and under-ground geological mapping studies, the continuation of the reverse circulation drilling, and the initiation of underground core drilling.

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District Geology
The district is located within a Precambrian metasedimentary roof pendant of the Idaho Batholith surrounded and intruded by Cretaceous tonalities, diorites, granodiorite and quartz monazite. The youngest intrusive rocks are granitic pegmatites of variable mineralogy. The Precambrian metasedimentary block is folded and fractured with a regional 25� to 40� N dip.

Preliminary structural geological mapping studies commenced in 2003, both from surface and under-ground, greatly enhancing knowledge of the geology and structural controls at the Kimberly. Results include the discovery of an additional mineralized vein as well as two skarn horizons, potentially providing the first bulk tonnage drill targets for the project.

Abundant evidence exists throughout the historic workings that structural geology plays a crucial role in understanding the mobilization and possibly remobilization of gold. The current work program at Kimberly will prioritize the expansion of the structural mapping programs.

Surface Mapping
A detailed surface geological map covering most of the project area was created during the 2003 work season [map]. This study successfully mapped the intrusive/metasediment contact, identified three major faults and eight individual stratigraphic units, and led to the discovery of two skarn horizons providing new potential bulk drill targets. It also identified surface exposures of the Gold Crest Vein, which returned sample grades up to 0.39 oz/t gold and 1.65 oz/t silver.

Potential drill targets at the Kimberly Gold Mine now include:

High grade gold in quartz veins that have been of historic interest and are the target of the current reverse-circulation drill program.
An easterly trending gold-bearing skarn bed estimated at roughly 20 feet in thickness, dipping at about 40 degrees in a northerly direction. The current drill program may intercept this bed at a depth of roughly 300 feet.
A mica carbonate schist that exhibits local skarn and replacement mineralization. This unit may exceed 200 feet in thickness, potentially constituting a bulk tonnage gold skarn target.

Besides the known potential of high-grade, narrow vein gold at the Kimberly, its carbonate-bearing stratigraphy enhances the likelihood of a bulk tonnage skarn deposit on the property. Ground magnetic and aeromagnetic surveys, together with remote sensing techniques, will be required to further define any bulk tonnage drill targets.

The skarn mineralization is intimately associated with the quartz monzonite. The skarn units consist of coarse grained Ca-Fe-Mg-Mn silicates formed by the replacement of carbonate bearing rocks. The reactive nature of carbonate rocks with magmatic fluids may form metalliferous deposits such as iron, tungsten, copper, lead-zinc, and tin. Precious metal deposits may form as variations within these skarn types.

Underground Mapping
The underground structural mapping program focused on areas within the Kimberly, New Fisher, and Gold Crest #1 tunnels. The study identified a second quartz vein within the Kimberly Tunnel, striking N25W compared to the main vein that strikes N70E. This discovery indicates the presence of unexplored veins striking orientations that run counter to the primary trend.

The underground structural mapping program at Kimberly has identified the following:

Quartz-gold-silver veins are controlled by joint and/or shearing in the folded metasediment roof pendant.
The veins were emplaced along pre-existing or syn-emplacement structures.
The veins are associated with intrusive dykes and sills and therefore may exist in the underlying pluton.

Previously explored mineralization at Kimberly occurs in moderately to steeply dipping parallel quartz veins with a general strike of N70� to 80� E and dips of 50� to 80� S. The ore contains free gold usually associated with limonite, pyrite and trace amounts of arsenopyrite, sphalerite, chalcopyrite, tetrahedrite and galena (Tekverk and Fay, 1983).

There are at least three primary veins on the Kimberly property (Gold Crest, Digger, and Hickson-Bishop), ranging from a few inches to several feet thick. Ore-shoots tend to swell and pinch along strike and down-dip. The known strike length of the veins is about 4950 feet for the Gold Crest, at least 660 feet for the Digger and up to 1320 feet for the Hickson-Bishop.

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Project History
The original Kimberly claims were located just north of Twin Lakes in the summer of 1900 by George Conners, Dan LeRoy, A.A. Easton, W.A. Scott and George A. Wright. The five men also located the Jewel Group one mile north of the Kimberly claims and had installed a two-stamp mill on the Jewel property by 1901. The Jewel Group was producing considerable rich, free-milling gold ore by 1902. Conners, Scott, and their partners located the Digger Vein on the Kimberly property, roughly 1000 feet west of West Twin Lake, in 1906 (Mitchell, 1994).

In 1911, the Idaho Inspector of Mines reported that the Gold Crest Vein was developed by several short adits to a depth of 165 feet. He also stated that an ore-shoot 281 feet long and varying from roughly 4 to 24 inches wide had been developed by these adits and that the vein was traced along the surface by several open cuts and rich float for over 2000 feet. The report goes on to state that numerous samples of the vein were said to contain up to 7.25 ounces per ton (oz/t) gold. By 1937, the 271-foot long, roughly one foot wide ore-shoot was being worked from open, overhand stopes through a short crosscut and drift along the vein. Kimberly Gold Mines Inc. (no relation to the present company) was organized in early 1938 to take over the operation of the mine (Lorain, 1938).

In 1940, a drift was run on the Digger Vein and the Crystal Tunnel was started, roughly 200 feet below the other adits. A 50-ton per day (tpd) flotation and amalgamation mill was built at the mouth of the Crystal Tunnel, commencing operation in June 1941, processing ore that assayed 2.21 oz/t gold. There were approximately 2,740 feet of workings on the property at that time. The mine continued to produce until October 1942 when War Production Board Limitation Order L-208 closed it for the duration of World War II. The mine remained closed until 1947 (Mitchell, 1994).

In 1948, a geological survey was conducted to prepare the mine for its reopening that summer. In 1949, the company cleaned out several caved adits and drove 565 feet of crosscut to intersect the ore-shoot at depth. In 1950, a diamond drill program was completed consisting of 603 feet of underground and 588 feet of surface drilling (Mitchell, 1994).

During 1954, an ore shipment was submitted for mill and metallurgical testing by Arthur D. Searle, with results indicating gold and silver recoveries of 97.6 and 84.9 percent, respectively. Between 1955 and 1958, the mill was expanded from 50 tpd to the present 100 tpd. By 1964, there were approximately 8745 feet of mine workings at Kimberly (Mitchell, 1994).

In 1975, Kimberly Gold Mines Inc. merged with Summit Silver Inc., which employed small work crews to conduct exploration and small development operations.

In 1977, the property was leased to Hub Mining and Exploration Ltd., of Vancouver. Hub conducted detailed assaying of the Gold Crest No. 2 adit and performed an internal resource and reserve estimate for the Gold Crest Zone.

In 1983 and 1984, the property was leased to Golden Resources Company which drove the New Fisher Tunnel over 660 feet. Additional drifting and sampling of the Kimberly/Gold Crest Vein was accomplished and the Hickson-Bishop No. 2 Adit was re-opened.

In 1999 Kimberly Gold Mines took control of the project.

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Project Details
Maps
Geology | Tunnels | Veins map
Click to view each map in a new window

The following provides additional exploration and historical details for each of the "tunnel areas" at the Kimberly Gold Mine.

Crystal and Digger Tunnels
The Digger Vein has been explored by a 660-foot long drift and by the Crystal Tunnel, some 230 feet below. The Crystal Tunnel also attempted to explore the down-dip extension of the Gold Crest mineralization.

In 1950, an 8-hole diamond drill program was completed, consisting of 604 feet of underground drilling and 588 feet of surface drilling. Unfortunately, there is little data available from this program. The only documents are a map showing locations of drill holes, driller's log sheets and a single assay sheet for one drill hole which indicated a poor core recovery due to broken ground and water. A sludge sample from 98 feet to 103 feet showed 10.5 oz/t gold and 2.3 oz/t silver.

In 1983, a dump sample collected by Tekwerk and Fay assayed 0.23 ounces per ton (oz/t) gold and 10.36 oz/t silver indicating that gold mineralization had been cut somewhere in the workings.

During 2002 and 2003, initial rehabilitation of the Digger Tunnel commenced. However, the presence of substantial volumes of water within the tunnel severely hampered progress.

In 2003, a series of grab samples were taken from the mine dumps of the Digger and Crystal Tunnels. At the Crystal dump, several different types of quartz vein material were observed, indicating that perhaps two or three different veins had been explored during past development. Grab samples assayed between 0.003 and 0.236 oz/t gold and between 0.08 and 5.06 oz/t silver.

Kimberly Tunnel
Around 1911, the Gold Crest Vein was first explored by the 400-foot long Kimberly Tunnel southwest of the "Camp" and just above the West Twin Lake water level.

In 1950, two surface diamond drill holes were completed just north of the Kimberly tunnel. These holes were apparently drilled in search of a down-dip extension of the Kimberly ore-shoot. A single cross-section illustrates an interpretation of the drilling results where it appears that the Kimberly workings are located in a large slide block and the vein was beginning to flatten at depth as it approached the normal fault. It is unknown if the drill holes reached the offset vein.

In 1968, an individual sample collected from stoped workings assayed 5.77 oz/t gold and 22.63 oz/t silver. In 1983, a dump sample assayed 0.67 oz/t gold and 0.64 oz/t silver indicating that mineralization had been cut somewhere in the workings.

In 2002, the Kimberly tunnel portal was rehabilitated and systematic channel sampling of the vein was performed, returning an average grade of 0.27 oz/t gold. Samples of vein material returned values up to 1.7 oz/t gold over 28 inches.

In 2003, the Kimberly tunnel was mapped and a second mineralized vein was found. Channel samples returned gold values of up to 0.63 oz/t gold and 3.36 oz/t silver. The company is developing a plan for further for exploration of Kimberly tunnel.

Fisher and New Fisher Tunnels
The Gold Crest Vein has also been explored by the Fisher and New Fisher tunnels. The Fisher Tunnel was driven in the 1930s, and the New Fisher Tunnel around 1984. The New Fisher Tunnel is located about 109 feet east of the Fisher Tunnel and 66 feet higher in elevation.

A 1939 plan map of the Fisher tunnel shows two assays indicating 3.3 feet of 0.87 oz/t gold and 1.0 feet of 2.41 oz/t gold, respectively. The weighted average of these two samples is 1.25 feet of 1.53 oz/t gold, equating to 0.58 oz/t gold over a one-meter (3.3 feet) mining width. These are located about 330 and 426 feet, respectively, from the main crosscut along the east drift. A small stope may have been mined in this area.

In 2003, an underground geological and structural mapping exercise was completed, indicating that the New Fisher Tunnel had not been driven far enough to intersect the Gold Crest Vein.

In 2005, an underground diamond drilling program was conducted to explore beyond the end of the New Fisher tunnel to test this theory. This drill program did intersect the Gold Crest Vein at 32 feet beyond the drift face.

Gold Crest Tunnels
The Gold Crest No. 1 Tunnel is located 396 feet east of the New Fisher Tunnel. The Gold Crest No. 2 Tunnel is located 66 feet below and 25 feet east of the No. 1 Tunnel.

Research by Arthur Smith (April 2002) located two documents that indicate significant mineralized tonnage on the property. It should be noted that the term "reserve," as used below, is not consistent with currently-accepted usage and is not endorsed by Kimberly geologists. This information is historical and has not been independently verified by Kimberly Gold.

In 2002, both of the Gold Crest portals were rehabilitated. A grab sample of material contained within one of the old ore shoots in the Gold Crest No. 1 returned values of 1.46 oz/t gold and 2.10 oz/t silver.

In 2003, an underground structural geological mapping program was conducted in both of the Gold Crest tunnels. A similar set of joints to those controlling the mineralization in the Kimberly tunnel were noted, indicating that a gold-bearing structure may be present, but is currently inaccessible.

Hickson-Bishop Tunnels
The Hickson-Bishop No. 2 and No. 1 tunnels are located 1600 feet and 2805 feet east of the Gold Crest No. 2 Tunnel, respectively. The Hickson-Bishop Vein appears to parallel the Gold Crest Vein and is located about 400 feet south. An historic map shows several raises along the vein for a strike length of 106 feet in the No. 1 Tunnel. Paul T. Benson sampled the raises and connecting stopes in 1963 and the arithmetic average of the five of the samples for which widths are stated was 0.36 oz/t gold over a 2.5-foot width. In 1968, limited sampling of the Hickson-Bishop No. 2 tunnel yielded an average result of 0.42 oz/t gold and 0.40 oz/t silver over a 3.3-foot width.

In 2002, the Hickson-Bishop No. 2 portal was rehabilitated and sampled with returned grades up to 3.12 oz/t gold and 1.9 oz/t silver, averaging 0.98 oz/t gold and 0.79 oz/t silver, over a 2-foot width.

In 2003, a bulk sampling study from the same area showed high-grade gold in both quartz and fault gouge, indicating that local faulting occurred post-mineralization. Subsequent metallurgical work that confirmed the need to incorporate both gravity and floatation circuits to achieve optimal mineral recoveries. Past production data has shown recoveries consistently above 90 percent without cyanide leaching.

Mount Marshall Mine Area
In 2002, the Kimberly Project was expanded to include the neighboring Mount Marshall Mine. This adds the gold-bearing "Mount Marshall Zone" to the project, just 3500 feet south of the "Kimberly Zone." The two mineralized zones run parallel to each other, as well as to all other known gold-bearing zones in the district. Historical data indicates that the Mount Marshall Mine was initially developed in 1908 and yielded free milling gold grading as high as 2.0 to 2.8 oz/t.

The Mount Marshall Mine is explored from surface by a vertical shaft of unknown depth. It is thought that this shaft intercepts the 700-foot long Lucky Strike Adit. In 2002, sampling of the surface vein exposure returned values of 0.05 oz/t gold and 0.52 oz/t silver and a grab sample from the Mount Marshall dump returned values of 0.27 oz/t gold and 2.32 oz/t silver.

A sampling program was conducted in the Mount Marshall area. Several bulldozer cuts have explored the surface outcropping of the Mount Marshall Vein near the shaft. Grab samples were collected from all cuts exhibiting vein exposure, and from those with significant mine dumps containing quartz material. These samples returned assays as high as 0.47 oz/t gold. Within the principal Mount Marshall dump, there are several different types of quartz mineralization, indicating that several different quartz veins may have been explored at depth.

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