Carnotite & Tyuyamunite — Big Indian Wash, San Juan County, Utah, USA. Ex. Mount Holyoke College Teaching & Research Collection

A large cabinet specimen of Carnotite and Tyuyamunite from Big Indian Wash in the Colorado Plateau uranium district of San Juan County, Utah — one of the classic American sedimentary uranium localities — bearing the distinguished provenance of the Mount Holyoke College teaching and research mineral collection.

Carnotite and Tyuyamunite are closely related potassium and calcium uranium vanadium oxide minerals respectively, occurring together in the characteristic yellow to greenish-yellow earthy to microcrystalline crusts and impregnations that define the secondary uranium mineral assemblages of the Colorado Plateau sandstone-hosted uranium-vanadium deposits. Big Indian Wash is a well-documented Colorado Plateau locality within the Paradox Basin, a region that produced some of the most significant uranium ore deposits in North America during the postwar uranium boom and remains a reference locality for sedimentary uranium mineralogy.

The institutional provenance of this specimen adds a dimension that separates it from anonymous collector material. Mount Holyoke College in South Hadley, Massachusetts maintains one of the oldest and most respected liberal arts geology programs in the United States, and specimens that passed through institutional teaching and research collections carry a documented history that is increasingly valued by serious collectors. Institutional deaccessions of this character are uncommon and represent an opportunity to acquire material with a traceable academic chain of custody.

Large cabinet specimens of Colorado Plateau Carnotite-Tyuyamunite association with documented locality data and institutional provenance are seldom encountered on the collector market. This piece is suitable as a centrepiece specimen for an advanced uranium mineral collection or as a reference specimen for researchers studying secondary uranium vanadium mineralogy of the American Southwest.

Carnotite and Tyuyamunite are radioactive minerals. Suitable for advanced collectors and researchers with appropriate handling and storage knowledge.

Locality: Big Indian Wash, White Canyon District, San Juan County, Utah, USA Provenance: Ex. Mount Holyoke College Teaching and Research Mineral Collection.

Approx. specimen size: 120mm x 90mm x 60mm

Approx. specimen weight: 730 grams

Approx. specimen activity on an SE International Ranger EXP: 82000 CPM