SUNSTONE

Photo courtesy of Scott Papper, GIA GG, AJP, CMA (NAJA), Global Gemology & Appraisals

Variety:  Sunstone
Species:  Labradorite
Group:  Feldspar
​​Mohs Hardness:  6 to 6.5 out of 10
Color:  Pale pinkish orange and pink to moderate and strongly saturated reddish orange, red-orange and deep red.  Red and green bicolor gems exist, but are extremely rare.
Phenomena:  Aventurescence
RI:  1.559 to 1.568 (+/-0.005), Oregon material commonly 1.563 to 1.572.
Birefringence:  0.009
SR/DR/AGG:  DR
Clarity Type:  Type II
Optic Character:  Biaxial positive (often shows twinning in the polariscope)
Pleochroism:  Oregon material might show very strong red and green pleochroism.
Spectrum:  Not diagnostic
Fluorescence:  Inert
SG:  2.70 (+/-0.05)

Sunstone Facts

Photo courtesy of GIA

​Sunstone is a variety of the feldspar-group mineral, labradorite.​


Sunstone possesses a phenomena known as "aventurescence".


Sunstone's signature glitter is caused by light reflecting off of tiny copper platelets.
 
The minerals in the feldspar family make up roughly 60% of the earth's crust.  Other varieties of feldspar include orthoclase, labradorite, moonstone & amazonite.