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)
Sulphur Bank Mine tin ore. Oxland believed the cinnabar ore at Sulphur Bank had been formed from hot springs. His thesis stated that hot springs brought metals in a dissolved state from igneous rock deep in the earth through a thick block of metamorphised ancient seabed to form cinnabar ore near the surface of the mine. Oxland also believed the cinnabar deposit was continually forming. Becker came to agree with the Oxland thesis. There were a number of mysteries about the Sulphur Bank that Becker attempted to solve. Among them was how sulfur had been delivered to the surface of the mine and