Bruneau jaspers : A Unique Gem in the Heart of Idaho.

3 days ago
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Credit photo : Hans Gamma, https://worldofjaspers.com/Idaho.html

Bruneau jasper is one of the most sought-after and expensive varieties of jasper, known for its distinctive patterns and fascinating geological origin. They are found at the confluence of the Bruneau and Jarbidge Rivers in Bruneau Canyon, approximately 35 miles from the village of Bruneau in Owyhee County, in southwestern Idaho, USA. These exceptional stones are highly prized by collectors and gem cutters worldwide.

Crédit photo : Emmanuel Thoreux

The colors of this jasper are incredibly varied, ranging from light brown to dark chocolate brown, with shades of reddish-brown and, at times, olive hues ranging from gray to black. Even rarer are blue-to-white specimens, which add a unique touch to this already exceptional stone. Bruneau jasper forms when colloidal silica and brownish silt mix and stabilize, creating these unique patterns and colors, as noted by Shaub in 1989.

Litho-physes can reach up to 25 cm in diameter, and the most prized specimens are those with sharp patterns and contrasting colors, often ranging from bright yellow to deep brown at the periphery. Due to their rarity and the difficulty of extraction, even broken pieces with well-defined patterns can fetch very high prices.

Bruneau Jaspers were discovered in the 1930s by Ruth and Sam Kirkby, a couple of collectors, before Snake River Pete revealed the location in 1960, after following the directions of a local shepherd. Over the decades, access to these precious jaspers has become increasingly difficult, as they are found in hard rock requiring considerable effort to extract.

The patterns of Bruneau jaspers are famous for their series of overlapping circles, more or less oval or round, creating a very distinctive three-dimensional effect.