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Danburite
Chemical Formula	CaB2(SiO4)2
Species	Silicates
Crystal System	Orthorhombic
Mohs Scale	7
Specific Gravity	2.99
Color	Pale yellow, yellowish-brown, colourless
Streak	White
Luster	Vitreous, Greasy
Refractive Index	n = 1.627 - 1.633 n = 1.630 - 1.636 n = 1.633 - 1.639
Diaphaneity	Transparent, Translucent
Cleavage	Poor/IndistinctIndistinct on
Fracture	Irregular/Uneven, Sub-Conchoidal
Crystal Habit：Prismatic crystals, disseminated masses.
Geological Setting：Granite and metamorphosed carbonates, evaporites.

Its chemical formula is CaB₂(SiO₄)₂. It has a Mohs hardness of 7 to 7.5 and a specific gravity of 3.0. The mineral has an orthorhombic crystal form. It is usually colourless, like quartz, but can be also either pale yellow, yellowish-brown, or pink. It typically occurs in contact metamorphic rocks.

It is named for Danbury, Connecticut, United States where it was first discovered in 1839 by Charles Upham Shephard.