
mineral
Jasper
Silicon Dioxide (Quartz variety, SiO2)
AI-generated identification · may be incorrectMohs hardness of 6.5 to 7; yellow, brown, red, or multicolored; vitreous to dull luster; microcrystalline (cryptocrystalline) quartz structure; conchoidal fracture with no true cleavage; specific gravity around 2.58 to 2.91
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Physical properties
Mohs hardness of 6.5 to 7; yellow, brown, red, or multicolored; vitreous to dull luster; microcrystalline (cryptocrystalline) quartz structure; conchoidal fracture with no true cleavage; specific gravity around 2.58 to 2.91
Formation & geological history
Formed through the silification of sedimentary or volcanic rocks where silica-rich fluids precipitate microcrystalline quartz in cavities or fractures, often during hydrothermal activity or diagenesis.
Uses & applications
Used in ornamental objects, cabochons, jewelry, carvings, and as a popular specimen for rock collectors.
Geological facts
Jasper has been used throughout human history since ancient times for seals, talismans, and decorative items. It is an opaque variety of chalcedony.
Field identification & locations
Can be identified in the field by its waxy-to-dull luster, microcrystalline texture, hardness that scratches glass, and conchoidal fracture. Found worldwide in riverbeds, alluvial deposits, and volcanic regions.