Phenakite

Description

A rare, highly refractive, beryllium silicate mineral that has been used as a gemstone. Phenakite occurs in the Ural Mountains, Norway (Kragerø), Brazil (Miguel de Piricicaba) and the U.S. (Colorado, Virginia). Phenakite can be colorless, pale yellow, pink or brown.

Synonyms and Related Terms

phenacite; beryllium silicate

Physical and Chemical Properties

• Hexagonal systems with flat rhombohedral or long prismatic crystals. Good cleavage in one direction.
• Fracture = conchoidal to uneven.
• Luster = vitreous.
• Streak = colorless.
• Translucent to transparent.
• Composition = Be2SiO4
• Mohs Hardness = 7.5 - 8.0
• Density = 2.97-3.00 g/ml
• Refractive Index = 1.654-1.670

Resources and Citations

• Mineralogy Database: Phenakite