Sunstone
Revision as of 07:21, 24 July 2013 by (username removed)
Description
An opalescent mineral that is used as a gemstone. Sunstones are translucent stones with an iridescent sheen due to the parallel arrangement of its crystals. They are usually a golden-brown with dark red hematite flakes. The iron oxide inclusions give the stone a reddish glow. Major deposits of sunstones occur in Norway (Tvedestrand), Russia (near Lake Baikal), and the U.S. (Pennsylvania, North Carolina). Moonstones are found in potassium (orthoclase) feldspars, while plagioclase feldspars (albite, oligoclase, or labradorite) produce sunstones.
Other Properties
triclinic prismatic crystals. Inclusions give spangled appearance.
| Mohs Hardness | 6.0 - 6.5 |
|---|---|
| Density | 2.56-2.76 |
| Refractive Index | 1.53-1.59 |
Comparisons
Properties of Common Gemstones
Authority
- R.F.Symmes, T.T.Harding, Paul Taylor, Rocks, Fossils and Gems, DK Publishing, Inc., New York City, 1997
- Encyclopedia Britannica, http://www.britannica.com Comment: sunstone" Encyclopædia Britannica [Accessed March 4, 2002-