Cinnabar akin to that of HgO: each Hg center has two short Hg−S bonds (each 2.36 Å), and four longer contacts (with 3.10, 3.10, 3.30, and 3.30 Å separations). In addition, HgS is found in a black, non-cinnabar polymorph (metacinnabar) that has the zincblende structure. Cinnabar generally occurs as a vein-filling mineral associated with recent volcanic activity and alkaline hot springs. Cinnabar is deposited by epithermal ascending aqueous solutions (those near surface and not too hot) far removed from their igneous source. It is associated with native mercury, stibnite, realgar, pyrite, marcasite, opal, quartz, chalcedony, dolomite, calcite and barite. Cinnabar is
Ore dock steel chutes. These chutes project out over the water at a slight angle from the sides of the docks. The hinged chutes, which are lowered to drop ore from the pockets into ships, are located at twelve-foot intervals over the length of the dock. This spacing is not coincidental, as the docks and the lakers they could load evolved together, and laker hatch spacing is typically 12, or on center. Since the late 1800s, ore docks have been a common sight in many Lake Superior ports of Minnesota, Wisconsin and especially Michigan. Rich iron ore deposits were first discovered in