Uraninite Crystals - Tripp Mine (Nu-Age Mine), Cardiff Township, Highlands East Township, Haliburton County, Ontario, Canada

UO₂

Uraninite crystals from the Tripp (Nu-Age) Mine in Cardiff Township, Ontario, Canada, are notable for their well-formed cubic and octahedral habits, often exhibiting a deep black color with a submetallic to greasy luster. These crystals are typically found in pegmatitic and hydrothermal vein settings, associated with granitic host rock. The uraninite from this locality is highly radioactive due to its uranium content and is often found alongside other uranium-bearing minerals such as allanite, zircon, and secondary uranium minerals like autunite and gummite. The Tripp Mine was one of several small uranium operations in the Bancroft region, a historically significant mining district known for its diverse and well-crystallized radioactive minerals.

Specimens from the Tripp Mine can display sharp crystal faces, though many are partially altered due to natural weathering. Some uraninite samples exhibit an unusual patina from oxidation, ranging from dark brown to yellowish hues when secondary uranium minerals form on their surfaces. The Bancroft area, including the Tripp Mine, has been a favorite among mineral collectors due to the richness of its pegmatites and the variety of rare minerals present. While the mine itself is long inactive, specimens from this locality remain sought after, particularly for their crystallinity and association with other pegmatitic minerals from Ontario’s uranium-rich deposits.

Approx. specimen size: 16mm x 10mm x 10mm

Approx. specimen activity on an SE International Ranger EXP: 14 000 cpm