Albite is a plagioclase
feldspar mineral. It is the sodium endmember of the plagioclase solid solutionseries. As such it represents a plagioclase with less than 10% anorthitecontent. The pure albite endmember has the formula NaAlSi3O8. It is a tectosilicate.
Albite crystallizes with
triclinicpinacoidal forms. Its specific gravityis about 2.62 and it has a Mohs hardnessof 6 - 6.5. Albite almost always exhibits crystal twinningoften as minute parallel striations on the crystal face. Albite often occurs as fine parallel segregations alternating with pink microclinein perthiteas a result of exolution on cooling.It occurs in graniticand pegmatitemasses, in some hydrothermalvein deposits and forms part of the typical greenschist metamorphicassemblage for rocks of originally basaltic composition.
It was first reported in 1815 for an occurrence in
Sweden. The name is from Latin, "albus" for the typical white color.
* [http://www.mindat.org/min-96.html Mindat data]
* [http://www.webmineral.com/data/Albite.shtml Webmineral data]
* [http://mineral.galleries.com/minerals/silicate/albite/albite.htm Mineral galleries]
Wikimedia Foundation. 2010.