Sassolite
Sassolite | |
---|---|
![]() Yellow sassolite | |
General | |
Category | Borate mineral |
Formula (repeating unit) | H3BO3 |
IMA symbol | Sso[1] |
Strunz classification | 6.AA.05 |
Crystal system | Triclinic |
Crystal class | Pinacoidal (1) (same H-M symbol) |
Space group | P1 |
Unit cell | a = 7.02 Å, b = 7.06 Å c = 6.59 Å; α = 103.65° β = 101.11°, γ = 59.98°; Z = 4 |
Identification | |
Colour | White to gray, may be pale yellow from included sulfur or pale brown from included iron oxides; colourless in transmitted light |
Crystal habit | As scaly pseudohexagonal crystals; ncrustations; platy; tabular; may be stalactitic |
Twinning | Around [001] as twin axis, common |
Cleavage | Perfect on {001}, micaceous |
Tenacity | Sectile |
Mohs scale hardness | 1 |
Lustre | Vitreous to pearly |
Streak | White |
Diaphaneity | Transparent |
Specific gravity | 1.46-1.50 |
Optical properties | Biaxial (-) |
Refractive index | nα = 1.340 nβ = 1.456 nγ = 1.459 |
Birefringence | δ = 0.119 |
2V angle | Measured: 5°, Calculated: 16° |
Solubility | Soluble in water |
References | [2][3][4] |
Sassolite is a borate mineral, and is the mineral form of boric acid. It occurs in volcanic fumaroles and hot springs, as well as in bedded sedimentary evaporite deposits.[2]
Its mineral form was first described in 1800, and was named after Sasso Pisano, Castelnuovo Val di Cecina, Pisa Province, Tuscany, Italy where it was found.[4] The mineral may be found in lagoons throughout Tuscany and Sasso.[3] Usually coloured white to gray, it is colourless in transmitted light, and can also take on a yellow colour from sulfur impurities, or brown from iron oxides.[2]
See also[]
References[]
- ^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ a b c Handbook of Mineralogy
- ^ a b Webmineral.com
- ^ a b MinDAT
External links[]
Media related to Sassolite at Wikimedia Commons
Categories:
- Borate minerals
- Triclinic minerals
- Luminescent minerals
- Minerals in space group 2
- Mineral stubs