sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Hardness: 6.5-7 on Mohs scale; Color: Reddish-brown, tan, and yellow tones; Luster: Dull to waxy; Structure: Microcrystalline (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.58-2.91

Hardness: 6
Color: Reddish-brown, tan, and yellow tones
Luster: Dull to waxy

Identified March 19, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through permineralization where organic matter (like wood) is replaced by silica-rich minerals over millions of years. This specimen displays the characteristic waxy, opaque texture of jasper often found in North American desert regions or ancient volcanic ash beds.

Uses & applications

Used primarily for lapidary work (jewelry, cabochons), home decor, and as a popular specimen for mineral collectors.

Geological facts

Jasper has been used by humans for thousands of years to create tools and weapons due to its ability to hold a sharp edge when fractured; this specific specimen appears to be highly silicated, possibly transitionary between common jasper and petrified wood.

Field identification & locations

Identify in the field by its hardness (cannot be scratched by a steel knife), smooth waxy feel on broken surfaces, and lack of transparency. Commonly found in the American Southwest, specifically Arizona, Utah, and Oregon.

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