Sunstone

Sunstone
General
Category	microcline or oligoclase and orthoclase variety
Formula (repeating unit)	(Ca,Na)((Al,Si)2Si2O8)
Crystal system	Triclinic
Identification
Color	Colorless, orange, yellow, red, green, blue, brown and copper shiller
Crystal habit	Euhedral crystals, granular
Twinning	Lamellar
Cleavage	001
Mohs scale hardness	6.0–6.5
Diaphaneity	Transparent to translucent and opaque
Specific gravity	2.64–2.66
Refractive index	1.525–1.58

Sunstone is a microcline or oligoclase feldspar, which when viewed from certain directions exhibits a spangled appearance. It has been found in Southern Norway, Sweden, various United States localities and on some beaches along the midcoast of South Australia.