From Greek " The oligoclase is a feldspar plagioclase. It is a variety of albite.
To know more about the mineralogy of Oligoclase, see Mindat.org->
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Oligoclase
- Translations : Oligoklas, Oligoclasita, 更长石
- Synonym : Amantice, Lluvia, Oligocalcite, Sodium Spodumene, Amansite, Amantite, Oligoalbite, Soda-Spodumène, Tschermakite
- Etymology : Du grec "Oligos" όλίγος = peu et "Klass" κλάσις = cassure, du fait de son clivage plus difficile que pour les autres feldspaths (groupe minéralogique auquel il appartient). From Greek "Oligos" όλίγος = little and "Klass" κλάσις = break, because of its cleavage more difficult than for the other feldspars (mineralogical group to which it is up).
- Discovery: 1826 by August Breithaupt
- Type localityDanvikstull, Stockholm, Södermanland, Sweden.
Gemological data
- Chemical formula : (Na,Ca)[Al(Si,Al)Si2O8]
- Hardness (Mohs) : 6 - 6.5
- Density : 2.63 - 2.66
- Refractive index : alpha 1.533-1.544, beta 1.537-1.548, gamma 1.542-1.552
- Birefingence : 0.008 - 0.009
- Crystal system : Triclinique
- Group : Feldspaths
- Mineralogical Class : Tectosilicates
The gallery
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