Sunstone (feldspar)
Consumer Information
What color is it?: As shown above sunstone will be gold to orange color with bright sparkle flashes showing from within the stone.
What is the story behind this gemstone?: Not to be confused with the synthetic goldstone that is a type of glass, sunstone is a type of oligoclase feldspar that has tiny hematite inclusions that reflects light in the sparkle pattern shown in the photograph above.
Can I wear it everyday?: Yes. This stone is usually cut en cabochon and wears very well.
Is it expensive?: It can be in the finer colors. The aventurescence or display of fire of sunstone will control the price.
Is it a birthstone?: No.
What do I need to know before going shopping?: Make sure you are shopping in a professional independent retail jewelry store. Natural sunstone is a true feldspar gemstone and will be available in a variety of colors and qualities. Some discount stores have offered the synthetic glass called goldstone as natural sunstone. Do not be misled. Stay with a professional retail jeweler with a qualified gemologist on staff to insure you are getting the real thing.
General Information
A rough sunstone shown above measuring approx. 1.5 inches in length
Source: United States, India, Russia, and other locations
Chemical: Na(AlSi3O8)Ca(Al2Si2O8) One of the sodium feldspar group.
Formation: Igneous rocks and other formations
Crystal System: Triclinic although rarely seen as crystals
Unusual Properties: Sparkles or aventurescence as seen in the specimens above.
Gemological Information
RI: 1.532 - 1.542
Birefringence: .010
Optic Character: U+
Specific Gravity: 2.64 +-
Hardness: 6
Transparency: Opaque
Special Identifying Properties and Tests: Sparkle of light is very indicative. Some specimens will have very visible but tiny hematite inclusions that cause the aventurescence. Inclusions are diagnostic to separate from glass goldstone.
Synthetics: None known at this time.
Imitations: Goldstone. A synthetic glass imitation that is readily identifiable by a 10x loupe by an experienced gemologist.