Uranothorite — Macdonald Mine, Hybla, Ontario, Canada

Uranothorite. Macdonald Mine, Hybla, Hastings County, Ontario, Canada. Grenville Province. Uranothorite from the Macdonald Mine at Hybla — a historically significant radioactive mineral locality in Ontario's Grenville Province and one of the well-documented thorium-uranium occurrences of the Bancroft-Haliburton district. The Macdonald Mine exploited a carbonatite-associated rare earth and radioactive mineral deposit, placing it in the same geological family as the broader cluster of Bancroft-area carbonatites that have made this region one of the premier destinations globally for collectors seeking uranium and thorium mineral species. Uranothorite (ThSiO₄ with substantial U⁴⁺ substituting for Th) is a tetragonal nesosilicate whose collector specimens are typically black to dark brown, heavily metamict, and distinctly heavy for their size — reflecting the high atomic mass of thorium and uranium in the structure. Hybla-area uranothorite often occurs in association with other REE-bearing and carbonatite-associated minerals, and specimens from this mine carry the strong locality provenance of a named, documented Ontario occurrence. This is a radioactive specimen. Uranothorite's elevated uranium content produces a stronger radioactive signature than pure thorite, and this specimen should be handled sensibly and stored in accordance with local regulations. Approx. specimen size: 70mm x 40mm x 30mm Approx. specimen weight: 130 grams Approx. specimen activity on an SE International Ranger EXP: 9300 CPM