Unakite
First discovered in the United States in the Unakas mountains of North Carolina, unakite is an altered granite composed of pink orthoclase feldspar, green epidote, and generally colorless quartz. It exists in various shades of green and pink and is usually mottled in appearance. In good quality unakite is considered a semiprecious stone, will take a good polish and is often used in jewelry and other lapidary work such as eggs, spheres and other carvings like animals. It is also referred to as epidotized granite. In some of the Blue Ridge occurrences an epidotized augen gneiss is present exhibiting foliation structures.
Unakite can be found as pebbles and cobbles from glacial drift in the beach rock on the shores of Lake Superior. It occurs in Virginia where it is found in the river valleys after having been washed down from the Blue Ridge Mountains. Unakite is not limited to the United States, and is reported from South Africa, Sierra Leone, Brazil, and China as well as the United States. Some material labeled unakite lacks the quartz and is more properly epidosite.
References
R. V. Dietrich Gemrocks: Unakite
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