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 Run Formation. The upper reaches of the stream flow over rock of the Burgoon Sandstone formation. Rock outcroppings are present in the watershed. The entire length of the stream flows over soil of the Deep-Wellsboro-Oquaga soil association, except for the headwaters, which are on soil of the Oquaga and another, minor soil association. Most of these soils are highly acidic. There is a bed of iron ore on Ore Run. The watershed of Ore Run has an area of . Ore Run is difficult to access. The Ore Run Falls are a cascade and slide waterfall on Ore Run. They are