Myrickite

Myrickite is a name used for both the agatized and opalized cinnabar materials. With a Mohs hardness of 7, the agatized form is a red-orange with bits of white, whereas the opalized material is orange and black and is 5 on the Mohs hardness scale. Although similar in color, this material should not be confused with the stone from China referred to as "Chicken Blood", as that material is a cinnabar stained serpentine with a hardness of 2.5-4. Unique to the United States, Myrickite is found at only one location in any quantity. During the early 1950s, Myrickite had been found in small quantities at the Manhattan Mine, located in Napa County, California, USA.