Copper Mountain; New York; Illinois; Miller; Texas Mine, Copper Mountain, Prince of Wales Island, Ketchikan District, Prince of Wales-Outer Ketchikan Borough, Alaska, USA

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The Copper Mountain Mine is on a large block of patented claims. The land around it has been conveyed to the Sealaska Corporation or is under application for transfer to them. The subsurface rights to the claim block are held by the Sealaska Native Corporation.
Location: This site is at the mine symbol at an elevation of about 3,300 feet on the USGS 1:63,360-scale topographic map, about 0.3 mile south-southwest of Copper Mountain. This is the location of the principal workings on the property. The workings are on a large block of claims that extend south to the head of Copper Harbor and north on the Copper Mountain ridge for some distance. There are numerous adits on the property and one long tunnel, as well as numerous pits and trenches. Maas and others (1995) include a detailed map of the surface and underground workings where most of the mining took place.
Geology: The deposits at the Copper Mountain Mine and the surrounding claim block are related to a north-trending tongue of altered Cretaceous granodiorite about 600 feet wide that is bordered on the east by hornfels and on the west by Late Proterozoic or Cambrian marble of the Wales Group (Wright and Wright, 1908; Herreid and others, 1978; Maas and others, 1995). The contacts of the granodiorite are marked by extensive skarn with various combinations of diopside, epidote, garnet, magnetite, and scapolite. The skarn locally is quartz veined and often includes masses of fractured marble. The skarn contains disseminations and irregular masses of chalcopyrite, which in places forms high-grade pockets; malachite and azurite are prominent in the surface workings. The Copper Mountain Mine was discovered in 1897 and by 1905, a substantial town, including a hotel, a 250-ton-per-day smelter, and numerous buildings had been erected at the head of Copper Harbor to service the mine; an aerial tram was built from the top of the Copper Mountain to the smelter to transport the ore; and the company had bought a coal mine and coke ovens in Washington to fuel the smelter. Most of the ore that was mined came from surface pits on the New York claims (where this site is located) on the ridge southwest of Copper Mountain. The skarn there locally contained small masses of chalcopyrite and copper carbonates that initially fed the smelter but did not provide sufficient tonnage to sustain its operation. A 3,100-foot tunnel was driven to test the intrusive-skarn contact about 1,000 feet below the surface workings. Numerous short adits and prospect pits also were driven on copper shows on the claims. Small masses of copper-rich material were found in the tunnel and in various other workings, but no substantial ore bodies were found. There were other minor workings to the south in this claim block, including the Texas claim, at an elevation of about 1,450 feet. The deposits are similar to the one at the Copper Mountain Mine, but none was of significant size. From 1903 to 1907, the Copper Mountain Mine produced 224,285 pounds of copper, 10,331 ounces of silver, and 145 ounces of gold from 5,678 tons of ore. However, in 1907 it became apparent that the mine could not furnish sufficient ore to support the smelter, nor could it ship ore economically. The mine was closed and by 1919 the physical plant was largely dismantled or abandoned, although a large claim block was patented in 1914. This is a classic example of a large mine plant and smelter that was developed in anticipation of ore that never materialized, as is well documented by Roppel (1991).
Workings: The Copper Mountain Mine was discovered in 1897 and by 1905, a substantial town, including a hotel, a 250-ton-per-day smelter, and numerous buildings had been erected at the head of Copper Harbor to service the mine; an aerial tram was built from the top of the Copper Mountain to the smelter to transport the ore; and the company had bought a coal mine and coke ovens in Washington to fuel the smelter. Most of the ore that was mined came from surface pits on the New York claims (where this site is located) on the ridge southwest of Copper Mountain. The skarn there locally contained small masses of chalcopyrite and copper carbonates that initially fed the smelter but did not provide sufficient tonnage to sustain its operation. A 3,100-foot tunnel was driven to test the intrusive-skarn contact about 1,000 feet below the surface workings. Numerous short adits and prospect pits also were driven on copper shows on the claims. Small masses of copper-rich material were found in the tunnel and in various other workings, but no substantial ore bodies were found. There were other minor workings to the south in this claim block, including the Texas claim, at an elevation of about 1,450 feet. The deposits are similar to the one at the Copper Mountain Mine, but none was of significant size.
Age: Copper skarn probably is related to a deeper phase of the Cretaceous granodiorite intrusion exposed at the surface.
Alteration: Extensive development of skarn at the periphery of a Cretaceous granodiorite intrusion.
Production: From 1903 to 1907, the Copper Mountain Mine produced 224,285 pounds of copper, 10,331 ounces of silver, and 145 ounces of gold from 5,678 tons of ore. However, in 1907 it became apparent that the mine could not furnish sufficient ore to support the smelter, nor could it ship ore economically. The mine was closed and by 1919 the physical plant was largely dismantled or abandoned, although a large claim block was patented in 1914. This is a classic example of a large mine plant and smelter that was developed in anticipation of ore that never materialized, as is well documented by Roppel (1991).
Reserves: None.

Commodities (Major) - Ag, Au, Cu
Development Status: Yes; small
Deposit Model: Copper skarn (Cox and Singer, 1986; model 18b).

Mineral List

Azurite

Chalcopyrite

Magnetite

Malachite

4 entries listed. 4 valid minerals.

References