Danburite is a rare collectible mineral. Used to obtain boron. High quality danburite crystals are used by jewelers.
You can see danburite stone for sale and buy it in the Minerals of Russia online store.
General | |
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Category | Tectosilicates |
Formula (repeating unit) |
CaB2(SiO4)2 |
IMA symbol | Dbu[1] |
Strunz classification | 9.FA.65 |
Dana classification | 56.3.1.1 |
Crystal system | Orthorhombic |
Crystal class | Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) |
Space group | Pnam |
Unit cell | a = 8.038(3), b = 8.752(5) c = 7.73 [Å]; Z = 4 |
Identification | |
Colour | Colourless, white, gray, brownish white, straw yellow |
Crystal habit | Euhedral prismatic crystals; disseminated masses |
Cleavage | {001} Poor |
Fracture | Subconchoidal to uneven |
Tenacity | Brittle |
Mohs scale hardness | 7 – 7.5 |
Lustre | Vitreous – greasy |
Streak | White |
Diaphaneity | Transparent to translucent |
Specific gravity | 2.93 - 3.02 |
Optical properties | Biaxial (+/-) |
Refractive index | nα = 1.627 – 1.633 nβ = 1.630 – 1.636 nγ = 1.633 – 1.639 |
Birefringence | δ = 0.006 |
2V angle | 88 to 90° measured |
Dispersion | r < v strong |
Ultraviolet fluorescence | Fluorescent and thermoluminescent (red); Short UV=violet blue; Long UV=blue to blue-green |