Bruneau jasper is a variety of the mineral jasper. It is a "picture jasper" – a jasper that exhibits particular patterns and colors – and is used as an opaque gemstone.
The stone exhibits layered patterns of brown, reddish brown and cream color,[1] or sometimes of red and green color.[2] It was discovered in the Bruneau River canyon in Idaho,[1] near the bottom of the canyon walls,[2] where the rhyolite in which the jasper occurs is exposed for a length of 8 kilometres (5.0 mi).[3]
As of 2009 Bruneau jasper was no longer in production, and was difficult to locate.[1]
References
^ abcCollings, Michael R. (2009). Gem lore: an introduction to precious and semi-precious stones (2nd ed.). Rockville, Md.: Borgo Press. p. 85. ISBN9781434457028.
^Bonnichsen, Bill; Kauffman, Daniel F. (1987). "Physical features of rhyolite lava flows in the Snake River Plain volcanic province, southwestern Idaho". Geological Society of America Special Papers (212): 122. CiteSeerX10.1.1.832.9736.