Bruneau Canyon Jasper is one of the most well known jasper's from Idaho. It is classified as one of the very fine grained porcelain jasper's, that take a very high polish. The Bruneau canyon rhyolite is some of the most silica-rich rhyolite in the area. The Bruneau jasper flow was the source of silica that filled gas cavities in the upper zones of the rhyolite. The most common base color of the Bruneau Jasper is a pleasing reddish brown mixed with Light tan and cream colored swirls that form concentric circles, ovals and kidney like patterns. There are also darker colors of the jasper that have darker browns. The tans border on yellow and greens and black are mixed in too.