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| Sunstone (Heliolite) from Kola Peninsula |
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More Sunstones on ebay auction |
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Sunstone - Heliolite en.wikipedia.org Sunstone, a feldspar exhibiting in certain directions a brilliant spangled appearance, which has led to its use as an ornamental stone. The effect appears to be due to reflections from enclosures of red haematite, in the form of minute scales, which are hexagonal, rhombic or irregular in shape, and are disposed parallel to the principal cleavage-plane. These enclosures give the stone an appearance something like that of aventurine, whence sunstone is known also as "aventurine-feldspar." It is not common, the best-known locality being Tvedestrand, near Arendal, in south Norway, where masses of the sunstone occur embedded in a vein of quartz running through gneiss. It is found also near Lake Baikal, in Siberia, and at several localities in the United States, notably at Middletown Township, Delaware County, Pennsylvania, and at Statesville in North Carolina.... The Vikings are rumored to have used the Sunstone to sense the polarization of skylight for navigational purposes.... http://www.mindat.org A variety of Oligoclase A variety of feldspar that has schiller as labradorite does, but with an orange/brown background color, and containing small hematite crystals that give it an additional sparkle. ... |
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