Mercury (element) long periods at elevated temperatures. It reverts to the elements upon heating near 400 °C, as was demonstrated by Joseph Priestley in an early synthesis of pure oxygen. Hydroxides of mercury are poorly characterized, as they are for its neighbors gold and silver. Being a soft metal, mercury forms very stable derivatives with the heavier chalcogens. Preeminent is mercury(II) sulfide, HgS, which occurs in nature as the ore cinnabar and is the brilliant pigment vermillion. Like ZnS, HgS crystallizes in two forms, the reddish cubic form and the black zinc blende form. The latter sometimes occurs naturally as metacinnabar. Mercury(II)
Ore shoot Ore shoot In mining and geology, an ore shoot is a long seam of mineral or metal bearing rock that can be profitable to extract. The term may have originated in the 17th and 18th centuries when various theories existed on the origins of ore deposits, including some that suggested they grew like trees. Tabular or sheet-like deposits of metalliferous ores often contain areas of enhanced metal content that are larger in one dimension than another. A structure may contain multiple ore shoots. A "vein," "lode" or other mineral-bearing structure could be thick, steeply inclined within the host rock, persisting