Talc Talc Talc or talcum is a clay mineral composed of hydrated magnesium silicate with the chemical formula HMg(SiO) or MgSiO(OH). In loose form, it is (in ratio with or without corn starch) one of the most widely used substances known as baby powder. It occurs as foliated to fibrous masses, and in an exceptionally rare crystal form. It has a perfect basal cleavage, and the folia are not elastic, although slightly flexible. The Mohs scale of mineral hardness, based on scratch hardness comparison, defines value 1 as the hardness of talc. Talc can easily be scratched by a fingernail. Talc
Temagamite Temagamite Temagamite is a bright white palladium mercury telluride mineral with a hardness of on the Mohs scale. Its chemical formula is PdHgTe. It was discovered at the Temagami Mine on Temagami Island, Lake Temagami in 1973, and it represents a rare mineral in the Temagami Greenstone Belt. It occurs as microscopic inclusions within massive chalcopyrite at Temagami in association with other rare tellurides: merenskyite, stützite, hessite and an unnamed Pd-Hg-Ag telluride. In addition to the discovery locality, it has been reported from the Stillwater igneous complex in Montana and the New Rambler copper–nickel mine in the Medicine Bow Mountains