Danburite
Danburite is a calcium boron silicate mineral with the chemical formula CaB₂(SiO₄)₂. It typically occurs as prismatic crystals with a vitreous luster.
Properties and Characteristics:
- Color: Colorless, white, pink, yellow-brown, or light brown. Coloration may be due to trace elements.
- Crystal System: Orthorhombic
- Hardness: 7 - 7.5 on the Mohs scale
- Luster: Vitreous
- Streak: White
- Diaphaneity: Transparent to translucent
- Cleavage: Indistinct on {010}
- Fracture: Uneven to conchoidal
- Specific Gravity: 2.97 - 3.03
- Refractive Index: 1.630 - 1.636
- Birefringence: 0.006
Occurrence and Formation:
Danburite is found in contact metamorphic rocks and in some granitic pegmatites. It is often associated with other minerals such as quartz, feldspar, topaz, and fluorite. Notable localities include Russia, Mexico, Japan, Myanmar, and Madagascar.
Uses:
Danburite is primarily used as a gemstone. Transparent, colorless or light-colored specimens are faceted for use in jewelry. It is also collected by mineral enthusiasts. Some believe it possesses metaphysical properties, though there is no scientific basis for these claims.
Distinguishing Features:
Danburite can be distinguished from other similar minerals by its hardness, crystal form, and optical properties. Its relatively high hardness (7-7.5) helps differentiate it from softer minerals.