The Copper Bell Mine
Sep 23rd, 2009 by C. Alexander Leigh
JG had become interested in the mine portal I showed him in the Reiter area. Users of this off-road area will probably be familiar with the mine, which has been giving me the heeby jeebies ever since I first stumbled on it and its never-ending flow of freezing cold air.
I did some digging and it wasn’t hard to identify the mine, which is the Copper Bell. Apparently it was originally mined around the turn of the century but was never particularly profitable. I have found references going back as far as 1905, but as follows is a particular account of the workings. From the description it is certainly bigger than I had guessed just looking at the portal, but then, what do I know about mines. In retrospect the portal is probably deeper than it appears and has just been filling with debris washed in from the stream.
Copper Bell
This deposit (also known as the Bunker Hill) ranks second among the properties of the Index District, only to the Sunset, in point of development. During 1905 the company erected a 50-ton concentrator and also a well-designed copper reverberatory furnace. Much surface and mine development work has since been acomplished. No important development has been undertaken in the last ten years, due to the failure, so far, to develop sufficient ore for profitable mining. A watchman is kept at the property and the camp is still in fair repair.
The holdings are five miles northwest of Index, or one mile west of and 1,000 feet above the siding of Reiter, on the main line of the Great Northern Railway. The acmp is connected with the railway by a narrow-guage surface tram.
The deposit is near a plunging contact between the older intruded schist and quartzite, with granodiorite. The plane of contact sets at a steep angle, and near the mine workings, trends north 40 degrees west. The ore occurs as irregular replacement lenses along a shear zone in the granodiorite. Heated ore carriers ascending along this zone have sought out the best cavities and there partly replaced the granodiorite with chalcopyrite, bornite, pyrite, magnetite, quartz and calcite. Along the zone the femic minerals in the granodiorite are chloritized and the fedlsparrs deeply altered to sericite and kaolin. A thin-section study of the material by Cambell revealed the presence of well-shaped crystals of tourmaline. Since magnetite is prominently associated with the ores, the discovery of a second high-temperature mineral furnishes cogent evidence that the ore body should be classified as a high-temperature deposit, and that it is directly related to the granodiorite batholith which encloses it.
The deposit is explored by a long adit which follows the shear zone, 2,000 feet in a northeasterly direction. Six hundred feet from the portal a short crosscut to the northwest encountered an ore-shoot roughly cylindrical in outline. Stopes were driven up to daylight on this ore and a winze sunk below the adit level. This is now under water but it is reported that the ore lens pinches down to a small streak in the bottom of the winze. Above the present face of the long tunnel a short upper tunnel discloses a smaller lens of ore. Some years ago the deposit was prospected with diamond drills.
The log of these holes is not availible; however, it is known that some of the drills showed copper mineralization.
The Metal Mines of Washington, Ernest N Patty, 1921
