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| | serpentine on Encyclopedia.com |
 | | Serpentine can be found in igneous rock, but it is more often a secondary mineral, usually resulting from the alteration of minerals or rocks containing magnesium, and it occurs very widely throughout the world, mainly as a product of metamorphism in rocks rich in olivine, pyroxene and amphibole. |
 | | Serpentine rocks and basalts in the central zone of the Appalachian Mts of the eastern United States represent sutures of old oceanic crust, known as ophiolites, crushed between colliding continents. |
 | | Serpentine rocks are classified as common serpentine and precious serpentine, the common serpentine being darker, less translucent, and sometimes impure. |
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