sedimentary

Jasper

Jasper (Cryptocrystalline Quartz, SiO2)

Hardness: 6.5-7. Color: Reddish-brown due to iron inclusions. Luster: Dull to vitreous when polished. Crystal structure: Trigonal (microcrystalline). Opaque with a conchoidal fracture.

Hardness: 6
Color: Reddish-brown due to iron inclusions
Luster: Dull to vitreous when polished

Identified May 5, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7. Color: Reddish-brown due to iron inclusions. Luster: Dull to vitreous when polished. Crystal structure: Trigonal (microcrystalline). Opaque with a conchoidal fracture.

Formation & geological history

Formed from the consolidation of microcrystalline silica, often in volcanic ash or sedimentary environments where mineral-rich fluids circulate. The red color suggests high iron oxide content deposited during formation.

Uses & applications

Used primarily in lapidary work for jewelry, cabochons, and decorative carvings. Also popular as a landscape stone and for meditation or metaphysical collecting.

Geological facts

Jasper has been used as a gemstone since antiquity; it was mentioned in the Bible and used in the Minoan civilization to create seals. Because it is so hard, it holds a very high polish.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), opaque nature, and smooth, waxy feel on broken surfaces. Often found in riverbeds or near volcanic outcrops.