sedimentary

Jasper with Quartz Druzy

Silicon Dioxide (SiO2)

Hardness: 6.5-7 (Mohs). Color: Variegated brown, tan, and cream with translucent white crystals. Luster: Vitreous to waxy. Crystal Structure: Hexagonal/trigonal. Cleavage: None (conchoidal fracture). Specific Gravity: 2.6-2.9.

Hardness: 6
Luster: Vitreous to waxy

Identified April 12, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the process of mineralization where silica-rich fluids permeate porous host rock or cavities. This specimen likely formed in a volcanic or sedimentary environment where microcrystalline quartz (jasper) and macrocrystalline quartz (druzy) co-precipitated.

Uses & applications

Used in lapidary arts for cabochons, jewelry, and as a collector's specimen. In industry, high-purity quartz is used in glassmaking and electronics.

Geological facts

Jasper is an opaque variety of chalcedony. When it features a crust of tiny crystals on its surface, it is referred to as 'druzy.' These specimens are highly prized by rockhounds for their unique texture and visual contrast.

Field identification & locations

Identify by its hardness (cannot be scratched by a steel knife), waxy luster, and the presence of small, sparkling crystal faces. Commonly found in riverbeds or near ancient volcanic outflows. Look for heavy, dense stones with a 'sugary' coating.

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