Pirquitas (sector Oploca, level 7 1/4), Jujuy, Argentina
Thumbnail, 1.2 x 0.8 x 0.6 cm
Ex. Dr. Werner Paar
ex. Dr. Werner Paar Collection. TOYOHAITE, a rare silver species, is super-rare. This specimen features several sub-mm but eye-visible brown crystals clearly contrasted upon the sparkling franckeite matrix. For a micro, but sized to see something readily, it is nice. This is the Ag-rich end member of the rhodostannite-toyohaite solid solution series. A very rare mineral originally described from the Toyoha mine in Japan where it occurred in microscopic grains only. For the first time, a new occurrence in Argentina provides eye-visible crystals of this species (to 1 mm), and associated with other rare minerals like pirquitasite, cylindrite and fizelyite-ramdohrite (probably present but not identified as such by analysis). The mineral has a "pseudo-cubic" shape and looks like pyrrhotite. Only very few specimens with crystals were recovered, mostly ending up with the specialist researcher Dr. Werner Paar in Austria for further study; and chances to find additional material are said to be almost none. A "must" for any collector of rare silver-species minerals. Crystals from this pocket were microprobed in his lab, and almost exaxctly correponds to the end member composition