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Mineral: quartz
Gem: polkadot jasper
Size: 26mm x 28 mm
Carat: 44.4ct
Cut: freeform cabochon
Origin: Oregon
General Info: Jasper is derived from the Anglo-French "jaspre", meaning "spotted stone". Jasper is usually formed from old sediments (or volcanic ash flows) that have been glued (and at times replaced) with silica.

Flow patterns of the original material are often easy to see. Many jaspers are know as picture jasper because they contain what appear to be small images of sand dunes, mountains, plains, and even sky. Since the original materials were likely cross bedded sediments, they often contain the structure they mimic.

Additional Information
Polkadot jasper is also referred to as polkadot agate. It seems to set in that nitch where sometimes the material is hard enough and semi-translucent so it is agatized. Other samples may be more granular and will often undercut in the final gem preparation stage, giving it a consistency more like a softer jasper. Even when the back ground is hard agate, the dots are often much softer.