Mineral description : Apophyllite

Apophyllite in prehnite from Bredsjönäs. Apophyllite in prehnite from Bredsjönäs. Apophyllite from Jalgaon, Maharastra, India.

Mineral class Silicates : Phyllosilicates : Serpentinite - talc - Pyrophyllite group

Chemical formula KCa₄F₂(Si₄O₁₀)₂*8H₂O

Crystal system

Habitus As tetragonal crystals with cube or octaedric form. Also as foliated massive aggregates.

Cleavage Perfect basally, uneven fracture.

Hardness 4.5-5

Density 2.33-2.37

Color Colorless to white, sometimes with a red, green or yellowish hue.

Streak White

Luster Vitreous.

Description

Occurance

Associates

Notes Colors the flame violet.
Soluble in hydrocloric acid.

Locations A rare mineral in Sweden.

Nordmarks mines, Värmland. Pyramidic or foliated crystal groups, often in cracks in the iron ore.
Utö iron mine, in the arkipelago of Stockholm. As clear to slightly read large crystals.
Bredsjönäs, Skottvång, Södermanland. As thick druses or spherical aggregates in holes in the rock.
Långban, Värmland. As thin pink foliated masses in andradite scarn.
Sörgruvan, Hällestad, Östergötland. Foliated masses together with calcite crystals.
Dannemora mines. In druses together with babingtonite.
Alnön, Sundsvall. In small amounts.

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Mineral group index.
Main index.

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axelsson@acc.umu.se

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Last changed : 1998-03-07

Mineral class	Silicates : Phyllosilicates : Serpentinite - talc - Pyrophyllite group
Chemical formula	KCa₄F₂(Si₄O₁₀)₂*8H₂O
Crystal system
Habitus	As tetragonal crystals with cube or octaedric form. Also as foliated massive aggregates.
Cleavage	Perfect basally, uneven fracture.
Hardness	4.5-5
Density	2.33-2.37
Color	Colorless to white, sometimes with a red, green or yellowish hue.
Streak	White
Luster	Vitreous.
Description
Occurance
Associates
Notes	Colors the flame violet. Soluble in hydrocloric acid.
Locations	A rare mineral in Sweden. Nordmarks mines, Värmland. Pyramidic or foliated crystal groups, often in cracks in the iron ore. Utö iron mine, in the arkipelago of Stockholm. As clear to slightly read large crystals. Bredsjönäs, Skottvång, Södermanland. As thick druses or spherical aggregates in holes in the rock. Långban, Värmland. As thin pink foliated masses in andradite scarn. Sörgruvan, Hällestad, Östergötland. Foliated masses together with calcite crystals. Dannemora mines. In druses together with babingtonite. Alnön, Sundsvall. In small amounts.