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)
Cinnabar moth moult (instars) they mainly feed on the leaves and flowers of the plant, and can be seen out in the open during the day. Like several other Arctiidae larvae, cinnabar caterpillars can turn cannibalistic. This is mainly due to lack of food, but they can eat other cinnabar larvae. Initially, the larvae are pale yellow, but later larval stages develop the jet black and orange/yellow striped colouring. They can grow up to , and are voracious eaters; large populations can strip entire patches of ragwort clean, a result of their low predation. Often, very few survive to the pupal stage,