Chalcedony with Colloidal Cinnabar
Chalcedony with Colloidal Cinnabar. Cinnabar is mercury sulfide, the primary ore of the metal. The host rock for mecury deposits at this site is a highly silicified rhyolite tuff, originally deposited as an ash fall in a lake within a collapsed caldera. The cinnabar in this deposit is characterized by trace amounts of chlorine which cause the bright red mineral to turn black very quickly after exposure to light, often within hours. In this freshly uncovered nodule, the cinnabar that previously had been exposed at the surface has already turned black. McDermitt Mine. Opalite District. Near McDermitt, Humboldt Co., Nevada.
Chalcedony with Colloidal Cinnabar
Chalcedony with Colloidal Cinnabar. Cinnabar is mercury sulfide, the primary ore of the metal. The host rock for mecury deposits at this site is a highly silicified rhyolite tuff, originally deposited as an ash fall in a lake within a collapsed caldera. The cinnabar in this deposit is characterized by trace amounts of chlorine which cause the bright red mineral to turn black very quickly after exposure to light, often within hours. In this freshly uncovered nodule, the cinnabar that previously had been exposed at the surface has already turned black. McDermitt Mine. Opalite District. Near McDermitt, Humboldt Co., Nevada.