Thornasite

Help improve this record

No owner is registered for this specimen yet. If it's yours or you know more about it, you can add the owner, provenance, publications and other details.

Sparse tiny gray micro crystals of thornasite on matrix with colorless micro crystals of natrolite. The identity of this has been confirmed. The specimen comes with several previous labels including one from the collection of Eric Laskowski. Located in Quebec, Canada, the Demix-Varennes quarry exposes the alkaline igneous rock of the Saint-Amable sill, a nepheline syenite intrusion rich in miarolitic cavities, fractures, and pegmatitic pods. Quarrying operations at the site uncovered these volatile-rich pockets, yielding an exceptional diversity of rare micro-minerals that quickly made the location famous among mineral collectors as a mini Mont Saint-Hilaire. Among the species found within this unique geological setting is thornasite, an extremely rare hydrous sodium thorium silicate mineral that forms small, translucent light-green to beige crystals in highly alkaline environments. Highly prized by micromount collectors, thornasite was first discovered in the region during the late 20th century, making specimens from the Demix-Varennes quarry notable prizes in classical Canadian mineralogy collections.