Product Details

Natural Rarest Bastnasite 1.70 Carats Gemstone Cushion Shape Bastnäsite — Rare Earth Carbonate Fluoride (Ce,La)(CO₃)F Bastnäsite is a rare-earth fluorocarbonate mineral crystallizing in the hexagonal system and belonging to the bastnäsite group. It is typically cerium-dominant, though lanthanum and other light rare earth elements may substitute within the structure. The mineral commonly forms in carbonatite and hydrothermal environments associated with rare-earth element enrichment. Transparent gem-quality material is extremely uncommon, with most specimens occurring as translucent to opaque crystals. Typical coloration ranges from yellow and honey-brown to orange and reddish-brown, controlled primarily by rare-earth element composition. Gemological Properties Crystal System: Hexagonal Hardness: 4–4.5 Refractive Index: ~1.72–1.82 Specific Gravity: ~4.9–5.2 Cleavage: Imperfect Luster: Vitreous to resinous Due to its relatively low hardness and rarity in transparent form, bastnäsite is primarily of mineralogical and collector interest rather than commercial jewelry use. Facetable specimens are rare and typically small.