sedimentary

Red Jasper (Polished)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Hardness: 6.5-7 on Mohs scale; Color: Deep red to brownish-red due to iron inclusions; Luster: Dull to vitreous; Crystal Structure: Trigonal (microcrystalline); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Deep red to brownish-red due to iron inclusions
Luster: Dull to vitreous

Identified June 18, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the deposition of silica in groundwater or hydrothermal fluids within volcanic ash or sedimentary beds. The red color is typically derived from oxidized iron (hematite) during its formation process occurring over millions of years.

Uses & applications

Extensively used in lapidary arts for jewelry, decorative carvings, and cabochons. It is also a popular collectible for 'healing stone' enthusiasts and as a gravel substitute in ornamental landscaping.

Geological facts

Jasper is an opaque variety of chalcedony. Historically, it was known as the 'great nurturer' and has been used by ancient civilizations for seal stones and amulets for thousands of years.

Field identification & locations

Identify in the field by its opacity (unlike translucent carnelian), its high hardness (doesn't scratch with a steel blade), and its smooth, waxy surface when river-worn. Common in areas with volcanic activity or ancient seabed deposits.

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