Bismutite Pseudomorphs after Bismuthinite Crystals from the Great Basin Mine, Gabbs Valley, Nye County, Nevada

摘要

The Great Basin mine is a locality the author has been enjoying periodically over the last fifteen years for its interesting mineralogy and continued ability to produce specimens of interest. Most notable are the bismutite pseudomorphs after bismuthinite, found in one narrow zone of coarse crystalline grossular garnet. Just recently, the finest specimens were discovered, and which are now the chief focus of this brief discussion. Located in the Gabbs Valley of Nye County are numerous types of ore deposits, including the largest operating magnesium mine in the United States, several oxidized silver-bearing base metal deposits, a large open pit iron mine, a valuable and deep fluorspar vein, as well as varied smaller tungsten deposits. It is from the latter that the bismutite pseudomorphs have been produced.