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JaspersJasper is an opaque, impure variety of quartz that is normally red, yellow
and brown in color. This mineral breaks with a smooth surface, and is
often used mainly for ornamentation or as a gemstone. It could be highly
polished and is used for vases, Types of jasperJasper could appear as an opaque rock of various shades of red due to the mineral impurities. More usually, jasper exhibits one and more type of pattern or even variation from formation processes. Most often, variations rise from flow patterns inherent in the precursor sediment and volcanic ash saturated with silica to form jasper, yielding bands, apparent channels, and even eddying swirls in the rock. The hue and saturation of color could vary across the material. Jasper can be permeated by dendrite minerals providing the appearance of vegetative growths. The Jasper could have been fractured and/or distorted after formation, later rebounding into the discontinuous patterns and filling with another material. Heat or environmental factors can have created surface rinds (such as varnish) or interior stresses leading to fracturing. Picture jaspers simultaneously exhibit several of these variations (such
as banding, flow patterns, dendrites and its color variations) resulting
in what appear to be scenes or images in a cut section (as in Biggs, Deschutes,
Owyhee, Poppy and other named types). Spherical flow patterns produce
the distinctive orbicular appearance (porcelain jaspers such as normal
Blue Mountain, Bureau and Willow Creek). Complex mixes of impurities produce
wild color variations (as in McDermott jasper). Healed fractures produce
brecciate jasper (such as Canyon Creek
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