Mineral description : Albite

Albite in the form of cleavelandite from Varuträsk.

Albite in the form of albitite from Varuträsk.

Albite crystals with asphaltite from Granmuren.

Mineral class	Silicates : Tektosilicates : Feldspar group.
Chemical formula	(Na,Ca)(AlSi3O8) (100-90% Na, 0-10% Ca)
Crystal system	Triclinic.
Habitus	Tabular to prismatic, commonly with polysyntetic twinning. Often occuring in lamellar aggregates (cleavelandite) or as grainy aggregates (albitite).
Cleavage	Perfect in one direction and good in another with 90 degrees angle. Often with fine striation on cleavages.
Hardness	6-6.5
Density	2.62
Color	White to colorless.
Streak	White
Luster	Vitreous to pearly. Transparent to translucent.
Description
Occurance	As a major part of many rocks, especially igneous rocks as granites, syenites and pegmatites.
Associates
Notes	Twinning often produces many layers on top of each other, each only a fraction of a mm to several mm thick. Theese layers can be seen as striations not only on the surface of the crystal, but also on cleavages. This is a characteristic sign of the plagioclase feldspar series.
Locations	A very common mineral. In the quartz - feldspar quarries of Bohuslän. Malmberget, Lappland. As crystal druses of up to 10 cm size. Varuträsk, Västerbotten. Commonly as aggregates of cleavelandite Väne Ryr quartz quarry, Vänersborg, Västergötland. As cleavelandite. Riddarho quartz quarry, Värmland. As cleavelandite.

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