sedimentary

Jasper-Agate

Silicon Dioxide (SiO2)

Hardness: 6.5-7 (Mohs); Color: Red, brown, yellow, and translucent orange; Luster: Waxy to vitreous; Crystal Structure: Microcrystalline/Cryptocrystalline; Specific Gravity: 2.6-2.65

Hardness: 6
Color: Red, brown, yellow, and translucent orange
Luster: Waxy to vitreous

Identified July 18, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Red, brown, yellow, and translucent orange; Luster: Waxy to vitreous; Crystal Structure: Microcrystalline/Cryptocrystalline; Specific Gravity: 2.6-2.65

Formation & geological history

Formed through the deposition of silica from groundwater in volcanic cavities or sedimentary layers. This specimen shows typical oxidation and iron staining common in alluvial or glacial deposits.

Uses & applications

Used primarily for lapidary work, jewelry (cabochons), and as a collector's specimen.

Geological facts

Jaspers and agates are technically the same mineral (chalcedony), but are distinguished by their transparency; jasper is opaque while agate is translucent. Many specimens found in North America were transported thousands of miles by glaciers.

Field identification & locations

Identify in the field by its waxy luster when wet, extreme hardness (it will scratch glass), and conchoidal fracture patterns. Frequently found in riverbeds, gravel pits, and along shorelines.