Mineral description : Babingtonite

Babingtonite from Grönsjöberget.

Mineral class Silicates : wollastonite group

Chemical formula Ca₂Fe²⁺Fe³⁺Si₅O₁₄OH or Ca₂Fe(Si₅O₁₄OH) or Ca₂(Fe,Mn)(Si₅O₁₄OH)

Crystal system Triclinic, class : /1, Space group P/1, Z=2

Lattice constants a=7.36 b=11.52 c=6.58 alpha=91º 31´ beta==93º 51´ gamma=104º 4´

Diffraction lines 2.75(100) 2.87(80) 3.12(70)

Optical constants alpha=1.720 beta=1.731 gamma=1.753 (+)2V=76º

Habitus Crystals short prismatic or platy. Also as radial aggregates.

Cleavage {001} perfect, {1/10} imperfect. Fracture uneven, brittle.

Hardness 5.5-6

Density 3.36

Color Black to brownish black.

Streak

Luster Vitreous.

Description

Occurance Mainly in cavities and cracks in granites, gneiss and trap rock.

Associates

Notes

Locations A rare mineral in Sweden, but a nice locality appeared a couple of years ago.

Dannemora mine, Uppland. As crystals up to 3cm with apophylite.
Grönsjöberget, Borlänge, Dalarna. As 0.5cm crystals with quartz.
Lane trap rock quarry, Westfield, Hampdon county, Devon, England. As fine crystals.
Also in Arendal - Norway, Italy and Germany.

To silicate index.
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Last changed : 1998-03-07

Mineral class	Silicates : wollastonite group
Chemical formula	Ca₂Fe²⁺Fe³⁺Si₅O₁₄OH or Ca₂Fe(Si₅O₁₄OH) or Ca₂(Fe,Mn)(Si₅O₁₄OH)
Crystal system	Triclinic, class : /1, Space group P/1, Z=2
Lattice constants	a=7.36 b=11.52 c=6.58 alpha=91º 31´ beta==93º 51´ gamma=104º 4´
Diffraction lines	2.75(100) 2.87(80) 3.12(70)
Optical constants	alpha=1.720 beta=1.731 gamma=1.753 (+)2V=76º
Habitus	Crystals short prismatic or platy. Also as radial aggregates.
Cleavage	{001} perfect, {1/10} imperfect. Fracture uneven, brittle.
Hardness	5.5-6
Density	3.36
Color	Black to brownish black.
Streak
Luster	Vitreous.
Description
Occurance	Mainly in cavities and cracks in granites, gneiss and trap rock.
Associates
Notes
Locations	A rare mineral in Sweden, but a nice locality appeared a couple of years ago. Dannemora mine, Uppland. As crystals up to 3cm with apophylite. Grönsjöberget, Borlänge, Dalarna. As 0.5cm crystals with quartz. Lane trap rock quarry, Westfield, Hampdon county, Devon, England. As fine crystals. Also in Arendal - Norway, Italy and Germany.