Allanite-(Ce) — York River, Near Bancroft, Ontario, Canada

Allanite-(Ce). York River area, Bancroft, Hastings County, Ontario, Canada. Grenville Province.

Classic Bancroft-district allanite-(Ce) from the York River area, one of the most prolific and historically collected mineral terrains in Canada. This specimen presents the characteristic black, resinous to pitchy masses of allanite-(Ce) typical of the region's pegmatitic and skarn-associated occurrences — dense, heavy, and often showing the slight alteration rind that forms on exposed surfaces over geological time as metamictization and oxidation slowly modify the outermost mineral.

The Bancroft area lies within the Central Metasedimentary Belt of the Grenville Province, a deeply eroded Proterozoic orogenic terrain where widespread carbonatite intrusion, pegmatite emplacement, and high-grade regional metamorphism combined to produce one of the world's most exceptional concentrations of rare mineral species. Allanite is a fixture of the local collector circuit and an important accessory mineral in many of the area's pegmatites, skarns, and calc-silicate gneisses — occurring in association with minerals such as titanite, apatite, zircon, fluorite, and the many uranium and rare earth species for which Bancroft is globally renowned.

Approx. specimen size: 45mm x 25mm x 20mm

Approx. specimen weight: 43.48 grams

Approx. specimen activity on an SE International Ranger EXP: 610 CPM