Great Bear Claim
Gunnison County, Colorado
Gold, Silver, and Copper
LODE, 20.66 acres
$9,000
History
In 1879 a prospector named Jacob Hess found a boulder at the confluence of Gold and Quartz Creeks that assayed 900 ounces of silver per ton. This triggered a rush and most of the important claims of the Gold Brick Mining District north of Quartz Creek were staked by the mid-1880’s. Prospectors fanned out regionally and discovered several promising gold leads south of Quartz Creek, one of which was the Great Bear.
The Great Bear Claim remained little more than a prospect until 1902 when a haul road was finally built to the mine and development proceeded in a major way. The mine was worked by an inclined shaft following a quartz vein up to 7 feet wide that contained rich oxidized gold ores containing over 1 oz/ton gold. By 1903 the shaft was 100 feet deep, from which short drift levels were extended northwestward totaling 500 feet at depths of 35, 50 and 85 feet. The vein in the drifts was up to 6 feet thick. The vein was so rich in the upper levels that it was stoped to the surface and averaged 1.2 oz/ton gold. Some of the ore contained high copper values in the form of chalcopyrite, running up to 12 wt% copper. The vein dips moderately to the southwest and the hanging wall schist south of the vein is heavily altered and quartz veined and contained rich pockets of ore up to 3 ounces of gold per ton. The shaft could not be sunk further than 100 feet due to water problems.
In May 1912, the Great Bear was sold to a wealthy cattleman, G.A. Quinby of Denver, for $35,000, or the modern equivalent of $1.02 million USD. Quinby hired the former millman of the prolific Homestake gold mine in South Dakota, William Gardner, to manage the new mine. A ten-stamp mill and amalgamating and concentrating plant were constructed 800 feet below the mine and the ore was transported down the hill by a series of aerial tram towers. A drainage tunnel was completed to dewater the mine and once the vein was located, it was found to average 2 ½ to 6 feet wide, with local blowouts up to 12 feet and averaged about 0.7 oz/ton gold with significant copper. Some shoots on the vein carried up to 4.1 oz/ton gold. The mill was increased to 20 stamps and a larger cyanide plant capable of treating 140 tons per day was installed. The mine was sold to George T. Edwards, a wealthy Englishman residing in Salt Lake City, who proceeded to mine a small amount of ore averaging ~ 1.0 oz/ton gold from 1913 to 1916 before closing the mine due to technical failures associated with the cyanide plant.
Gold Potential
The Great Bear vein can be traced at the surface through float and overgrown prospect workings the entire length of the claim and as exposed underground, a high-grade central shear zone averaging >0.5 oz/ton Au up to 12 feet wide is enclosed within a broad envelope of mineralized and altered schist at least 35 feet wide. The vein is extremely rich in shoots containing visible free gold.
A considerable amount of free gold can be panned from the surface soils around the old shaft and collapsed stope. Test pans of soil and decomposed rock collected at numerous places around the mine contain up to 30 colors per pan, including a few ragged flakes. Around 35 significant surface cuts exist on the Great Bear vein on the property that have been mapped by Outwest geologists. Pans taken from old ore stockpiles and spilled ore around the tram towers and in the bed of the haul road between the mine shaft and tunnel contain significant free gold. A mini-bulk sample run through a sluice box produced almost 1/10 of an ounce of gold! A few specimens of rusty gossaniferous rock with free gold in limonite boxworks have been found next to the uppermost tram tower and some beautiful chalcopyrite specimens have been found in the road that likely spilled off the old wagons over 100 years ago.
To confirm the historic high-grades reported for the mine, 35 samples of average ore collected around the original shaft and in small stockpiles at the uppermost tram tower were assayed by Outwest for gold and silver. The average of these 35 samples is 1 oz/ton gold and no sample contained less than 0.17 oz/ton gold. Ten samples contained over 1 oz/ton gold, up to 9.99 oz/ton gold! The samples also contained up to 5.5 oz/ton silver. Many pieces contain visible free gold. It is estimated that at least 2,000 tons of ore of this quality exists in small stockpiles and surface wash around the mine workings, which has significant potential value at today’s $1,800 USD gold price, in excess of $3.5 million.
