Glittering Stones >> Semi
precious stones >> Feldspar
Semi Precious Stone Feldspar
Feldspar was collected by Apollo 16 from the Lunar Highlands near Descartes
Crater. This sample is currently on display at the National Museum of
Natural History in Washington, DC. Feldspar is the name of a very important
group of rock-forming minerals that make up perhaps as much as 65% of
the Earth's crust. Feldspars crystallize from magma in
the both intrusive
and the extrusive rocks; they occur as compact minerals, as veins, and
are normally present in many types of metamorphic rock. Rock formed entirely
of plagioclase feldspar (see below) is called as anorthosite. Feldspars
are also found in most types of sedimentary rock.
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Historical Facts of Feldspar
| Hardness |
6 on Mohs scale |
| Mineralogical composition |
Orthoclase, Albite and Anorthite |
| Groups |
Plagioclase feldspars, Alkali feldspars |
| Color |
Off-white,yellowish, flesh pink, brown or green |
| Uses |
Thermoluminescence dating and optical dating in earth sciences and archaeology |
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Gemstone Feldspar Jewelry
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