0971 Chrysothallite, Belloite, Avdoninite, Chlorothionite, Second scoria cone, Northern Breakthrough (North Breach), Great Fissure eruption (Main Fracture), Tolbachik volcano, Kamchatka Oblast’, Far-Eastern Region, Russia

Another NEW SPECIES from this bizarre geological environment in Kamchatka, chrysothallite occurs as extremely small, bright golden yellow, equant micro crystals perched in scoria vugs, often with olive green belloite and occasionally other rare species such as deep green avdoninite, blue chlorothionite etc. Formula: K6Cu6Tl3+Cl17(OH)4*H2O, tetragonal, IMA #2013-008. Named for the Greek word for gold and in allusion to its essential thallium content, only the second mineral with species-defining trivalent thallium.

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