calcite - typical metallic vein calcite from the Silver Spoon Mine - hand/display specimen
Students are most likely to see the cleavage rhombs of clear or white calcite, but in the field, this is not what they would see. Often, the calcite is dark, not clear or transparent, and it is one of the gangue (non-economic) minerals associated with mineralized veins. It can be difficult to see the three directions of cleavage unless a piece is broken by the student's rock hammer, but calcite is readily identified by its effervescent reaction to hydrochloric acid. The Silver Spoon Mine, in the Darwin lead, silver and zinc mining district of Inyo County, California, was a small lead, silver, zinc and gold mine active sporadically from 1929 to 1951. The orebody was 1.83 meters thick, plunged almost vertically, and was followed down by the miners. The field photos show the head of the 75˚ inclined shaft that followed the orebody and the remains of the chute that carried ore from the mine to a truck waiting in the canyon below. The pencil is 5.5" long, for scale. Select a specimen: