sedimentary
Jasper
Microcrystalline Quartz (SiO2)
Hardness of 6.5 to 7 on the Mohs scale, predominantly yellow-brown to greenish-brown color in this specimen, waxy to dull luster, cryptocrystalline or microcrystalline crystal structure, conchoidal fracture with no true cleavage, and specific gravity around 2.65.
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Physical properties
Hardness of 6.5 to 7 on the Mohs scale, predominantly yellow-brown to greenish-brown color in this specimen, waxy to dull luster, cryptocrystalline or microcrystalline crystal structure, conchoidal fracture with no true cleavage, and specific gravity around 2.65.
Formation & geological history
Formed through the silification of sedimentary rocks or volcanic ash, where silica-rich fluids replace original material over millions of years, commonly found in sedimentary basins and hydrothermal environments.
Uses & applications
Used primarily in ornamental carvings, cabochons, polished stones, jewelry, and as a collector's specimen.
Geological facts
Jasper has been used throughout human history since ancient times for amulets, seals, and tools. The region near São Paulo, Brazil (indicated by the coordinates), is exceptionally rich in various forms of chalcedony, agate, and jasper.
Field identification & locations
Identified in the field by its opacity, smooth waxy feel when polished, and conchoidal fracture. Found worldwide in riverbeds, alluvial gravels, and ancient sedimentary formations.
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