1. Education


Sulfide Mineral Pictures


Cinnabar, mercury sulfide (HgS), is the principal ore of mercury. (more below)
Mercury sulfide
Photo (c) 2009 Andrew Alden, licensed to About.com (fair use policy)
Cinnabar is very dense, 8.1 times as dense as water, has a distinctive red streak and has hardness 2.5, barely scratchable by the fingernail. There are very few minerals that might be confused with cinnabar, but realgar is softer and cuprite is harder.

Cinnabar is deposited near the Earth's surface from hot solutions that have risen from bodies of magma far below. This crystalline crust, about 3 centimeters long, comes from Lake County, California, a volcanic area where mercury was mined until recently. Learn more about the geology of mercury here.

Other Hydrothermal Vein Minerals

  1. About.com
  2. Education
  3. Geology

©2014 About.com. All rights reserved.