Uranothorite Crystal — Yates Mine, Pontiac County, Quebec, Canada

Uranothorite, crystal. Yates Mine, Pontiac County, Quebec, Canada. A sharp crystal of uranothorite from the historically significant Yates Mine — one of the canonical Canadian localities for the thorium-uranium silicate series. Uranothorite is the uranium-enriched end-member of the thorite group (ThSiO₄), a tetragonal nesosilicate in which thorium is progressively replaced by uranium. At elevated uranium substitution levels the mineral is designated uranothorite, and specimens from the Yates Mine are well-known in the collector community for offering exactly this: dark, heavy, typically metamict crystals with a strong radioactive signature considerably above that of pure thorite. The Yates Mine is situated in the Grenville Province of western Quebec, in a geological setting broadly comparable to the classic radioactive mineral occurrences across the Ottawa Valley and Bancroft terrain of Ontario. The mine worked carbonatite-associated and pegmatitic zones bearing thorium, uranium, and rare earth minerals. The thorite/uranothorite crystals found here typically occur as isolated, tetragonal prisms or pyramidal forms, often partially to fully metamict, jet-black to brownish-black in colour, with a high specific gravity immediately apparent when the specimen is handled. This is a genuinely radioactive specimen. The elevated uranium and thorium content produces a measurable gamma and beta signature. Locality: Yates Mine, Pontiac County, Quebec, Canada. Approx. specimen weight: 0.48 grams Approx. specimen activity on an SE International EXP: 6800 CPM