The Gemstone Sunstone
Sunstone is an interesting feldspar gemstone with a glittery appearance and usually an orange or reddish color, hence its name. The glitter effect is caused by inclusions of the mineral Hematite, or sometimes also Goethite or Pyrite (and in one rare instance, Copper). The term used to describe the glittery effect exhibited on Sunstone is aventurescence.
Color
?
Red, Orange, Brown, Pink
Chemical Formula
?
Microcline: KAlSi
3O
8
Oligoclase: (Na,Ca)Al
1-2Si
3-2O
8
Additional Properties
|
Refractive Index
?
1.525 - 1.548 |
Double Refraction
?
0.01 |
Transparency
?
Transparent to translucent |
SG
?
2.62 - 2.65 |
Luster
?
Vitreous |
| Cleavage ?
2,1 - basal ; 2,1 - prismatic ; 3,1 - pinacoidal |
All About
Sunstone is very similar in habit to
Aventurine, a form of
Quartz that exhibits the same glittering
Aventurescence effect. Sunstone is occasionally called 'Aventurine Feldspar' to distinguish it from its Quartz counterpart. However, Sunstone is always an orange or reddish color, whereas Aventurine, while sometimes occurring as orange or red, is most often green.
The glitter effect on Sunstone is usually red, orange, or golden yellow. It may also be green or blue, but this is very rare. Sunstone sometimes displays
asterism in the form of four-rayed stars, and these stones are known as
Star Sunstone. Sunstone occassionally also displays a
cat's eye effect.
Uses
?
Sunstone that is opaque is cut into
cabochons or polished into beads, and is used for necklaces, bracelets, and ornamental objects. The transparent forms of Sunstone or faceted into gemstone cuts for jewelry such as rings, earrings, bracelets, etc.
Treatments & Enhancements
?
Sunstone gemstones are not treated or enhanced.
Sunstone Sources
?
Sunstone sources are in India, Norway, Russia, Madagascar and the United States (Oregon).
Similar Gemstones
?
Sunstone may closely resemble orange
Aventurine, but Aventurine is slightly harder and is rare in colors other then green.
Sunstone in the Rough Photos
?