Cinnabar has been the major source of mercury throughout time.

Chemical Formula: HgS
Class: Sulfide of Mercury
Hardness: 2-2.5
Coloration: Bright to pinkish red

How to identify it/Unique Characteristics or Properties: Cinnabar has been the major source of mercury throughout time, and was often used both for its mercury and for a dye due to its bright red color. Of course, due to its toxicity, its use as a dye has died out. Cinnabar rarely comes in crystals, and those are usually quite small.

Where to find it in…

The Northwest: Jefferson County, Oregon
Other: Spain, Peru, Egypt, Italy.
Past Uses: Cinnabar was the coloration in vermilion dye, and is the major source of mercury today.
How it was Made: Forms in deposits near hot springs or in veins within volcanic rock.
Interesting Facts: Cinnabar is a major mercury ore, and one of the interesting uses of mercury is that it dissolves many other metals and forms amalgams with them. The mercury can then be removed, leaving pure metal. This is especially common in gold mining.