sedimentary

Fancy Jasper (Agate/Chert mix)

Silicon Dioxide (SiO2) with impurities

Hardness: 6.5-7 on Mohs scale. Color: Multicolored mottled patterns of ochre, brown, and translucent grey. Luster: Waxy to vitreous when polished. Crystal structure: Cryptocrystalline. Cleavage: None (conchoidal fracture).

Hardness: 6
Luster: Waxy to vitreous when polished

Identified March 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed from the deposition of silica in cavities or through the replacement of organic materials. The presence of iron oxides (hematite/goethite) creates the earthy yellows and reds. These can range from hundreds of millions of years in age.

Uses & applications

Commonly used for lapidary work, jewelry (pendants, beads), cabochons, and decorative ornamental carvings. It is valued by collectors for its unique 'earthy' aesthetic patterns.

Geological facts

Jasper has been used since antiquity for seals and talismans. Legend has it that 'Fancy Jasper' provides tranquility and wholeness, though geologically it is simply a colorful microcrystalline quartz.

Field identification & locations

Can be identified in the field by its hardness (cannot be scratched by a steel knife), smooth waxy feel, and opaque to semi-translucent internal patterns. Found globally, especially in India, Brazil, and the USA.

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