Sunstone is a plagioclase, also known as sunstone, sunstone, and gold-dust-effect feldspar. It is the most important variety of sodium olivine. Some aspects show a shining appearance, so it is regarded as a gemstone. Sunstone is found in western Norway and some places in the United States. It is also the state stone of Oregon.
Sunstone shows golden to orange-yellow flashes, which is called gold-dust-effect, a special optical effect of gemstones. It comes from the large number of oriented metal mineral flakes, such as hematite and goethite, contained in sodium olivine, which will produce reflections as the gemstone rotates.
Sunstone is colorless and transparent. It is extremely important to evaluate the transparency of sunstone. The more transparent the gemstone is, the higher its value. Yellow to orange, translucent, and dark inclusions with good reflective effects are the best sunstones.