sedimentary

Jasper with Quartz inclusions

Silicon Dioxide (SiO2) - Microcrystalline Chalcedony

Hardness: 6.5-7 (Mohs); Color: Reddish-brown matrix with white inclusions/veins; Luster: Vitreous to waxy; Crystal structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.58-2.91

Hardness: 6
Color: Reddish-brown matrix with white inclusions/veins
Luster: Vitreous to waxy

Identified February 21, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the process of silica precipitation from hydrothermal fluids or as a result of petrification. This specimen likely formed in an environment where iron oxides colored the microcrystalline quartz red, while later secondary quartz filled cracks or voids, creating the white patterns.

Uses & applications

Used primarily for lapidary work, jewelry making (cabochons), interior decoration, and as a popular specimen for amateur rock collectors and metaphysical use.

Geological facts

Jasper is often called the 'supreme nurturer.' The red coloration is typically caused by inclusions of hematite (iron oxide). It is an incredibly durable stone that has been used for making tools and seals since antiquity.

Field identification & locations

Identify in the field by its opaque nature, high hardness (will scratch glass), and smooth, shell-like (conchoidal) fracture surfaces. Commonly found in riverbeds and desert pavement areas in the Southwestern United States.

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