Leifite-Eirikite group

A well-composed miniature featuring a compact radial spray of acicular leifite crystals forming a tight, fibrous bundle, with a contrasting aegirine crystal penetrating the aggregate. The leifite displays its characteristic radial habit, forming delicate, tightly packed radiating prisms with a subtle silky lustre.

From Mont Saint-Hilaire, Québec, this specimen represents a classic assemblage from one of the world’s most important peralkaline intrusive complexes. Leifite is a rare beryllium-bearing tectosilicate with a framework structure of interconnected (Si,Al)O₄ tetrahedra, but unlike most tectosilicates, it does not fall within the feldspar or zeolite groups. It is structurally related to eirikite and forms under highly alkaline, volatile-rich conditions characteristic of the Mont Saint-Hilaire environment. Named after Leif Eiriksson, the Norse explorer. Fine, well-crystallized examples such as this are uncommon and desirable for advanced locality or species collections.