| Possibly the best examples in the U.S. of talc ore bodies formed by contact metamorphism are 45 deposits that have been mined and prospected in the southern Death Valley region, California. Twenty of the talc mines and prospects, all inactive, are located inside the boundaries of Death Valley National Park. The lead author sampled talc-rich rock and associated rocks in road cuts, and abandoned mine dumps and open pits at former talc mining operations within Death Valley National Park and at areas east of the park. Our mineralogical analyses of the talcose ores revealed that they contain a considerable proportion of tremolite, and locally the tremolite and associated sodic-calcic amphiboles intergrown with the talc occur as asbestiform particles. |
