Sunstone
Variety of feldspar
Uncommon · (Na,Ca)(Al,Si)₄O₈
Feldspar with aventurescence caused by reflections from platelets of hematite or goethite within the crystal. In Oregon sunstone, a labradorite from basalt flows, the platelets are native copper instead.
Identity
- Formula
- (Na,Ca)(Al,Si)₄O₈
- Chemical class
- Silicate
- Mineral group
- Albite, Labradorite, Moonstone, Orthoclase
- Also known as
- Aventurine feldspar, Heliolite
Crystallography
- Crystal system
- Triclinic
- Habits
- Tabular, Massive
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 6.5
- Density
- 2.65 g/cm³
- Luster
- Vitreous
- Colors
- orange, red, yellow, colorless, pink
- Streak
- white
- Transparency
- Transparent, Translucent
Geology
- Origins
- Igneous
- Host rocks
- Granite, Volcanic rock, Schist and gneiss
- Associated minerals
- Quartz, Orthoclase, Tourmaline, Hematite
- Found in
- Pegmatite deposit
- Geography
- Norway, India, USA (Oregon), Australia
Classification
- Rarity
- Uncommon
- Gem quality
- Yes
Arcane properties
- Affinity
- Fire, Light
- Effects
- Elemental fire
- Planar origin
- Material Plane
Sources
- Sunstone. Mindat.org (Hudson Institute of Mineralogy).
- Sunstone. Gemdat.org (Hudson Institute of Mineralogy).
- Sunstone. Gemological Institute of America, Gem Encyclopedia.
- Sunstone Description. Gemological Institute of America, Gem Encyclopedia.
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Oligoclase. Mineral Data Publishing, Handbook of Mineralogy, 2001.
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