Jasper is an opaque, impure
variety of silica found in a large variety of colors and patterns. It takes
a high polished and is used for ornamentation or as a gemstone. Jasper was
commonly used and a favorite gemstone in ancient times. Patterns in the
stone are caused in it's formation by the flow patterns in sediment or
volcanic ash inundated with silica. The jasper may have been fractured or
distorted after formation, later bonding into irregular patterns or filling
with another material.
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