Fourmarieite and Curite on Gummite/Uraninite - Ruggles Mine, Grafton, New Hampshire, USA

A classic secondary uranium mineral assemblage from the Ruggles Mine, North America's first commercial mica mine and one of the best-known U.S. localities for uranium mineral collectors. Ruggles sits in a Devonian-age granite pegmatite, and the uraninite (UO₂) it hosts has been weathering in place for millions of years, producing the colorful alteration crust collectors and mineralogists loosely refer to as "gummite", not a distinct mineral species, but a fine-grained mix of secondary uranium oxides and silicates including curite, fourmarieite, clarkeite, kasolite, and others, formed as groundwater slowly hydrates and oxidizes the primary uraninite.

This specimen shows both fourmarieite and curite developed on/around a gummite-uraninite core, giving a nice visual cross-section of the alteration sequence from black primary uraninite through to the orange-yellow secondary crust. A good study piece for anyone interested in uranium mineral paragenesis.

Approx. specimen size (mm): 65mm x 45mm x 40mm

Approx. specimen weight (g): 249 grams

Approx. specimen activity on an SE International Ranger EXP: 141000 CPM

Radioactive Mineral Shipping Policy

All naturally radioactive mineral specimens are available for shipping within Canada only. Due to Transport Canada dangerous goods regulations and Canadian Nuclear Safety Commission requirements, we cannot ship radioactive materials internationally. All specimens are packaged in accordance with excepted quantity guidelines and clearly labeled. Purchasers are responsible for ensuring they are legally permitted to possess radioactive mineral specimens under applicable provincial and federal regulations. If you have questions about a specific specimen's activity level or shipping eligibility, please contact us before purchasing.