sedimentary

Jasper

Silicon dioxide (SiO2)

Hardness: 6.5-7 (Mohs); Color: Pale grey/white with tan/yellow branching veins; Luster: Vitreous to waxy (especially when polished); Crystal Structure: Microcrystalline/Cryptocrystalline (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.9

Hardness: 6
Color: Pale grey/white with tan/yellow branching veins
Luster: Vitreous to waxy (especially when polished)

Identified April 5, 2026More sedimentary →

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Physical properties

Formation & geological history

Usually forms from the accumulation of silica in sedimentary environments or through the replacement/silification of other materials. Often found in proximity to volcanic activity where silica-rich fluids permeate porous rocks.

Uses & applications

Used primarily in lapidary arts for cabochon making, decorative tumbled stones, and energy healing collections. Historically used for making tools due to its hardness and fracture pattern.

Geological facts

Jasper is an opaque variety of chalcedony. The specific appearance of this specimen, with its distinctive 'veins,' is often referred to as 'Spiderweb Jasper' or sometimes 'Zebra Jasper' depending on the specific pattern intensity.

Field identification & locations

Identify by its opacity (it does not pass light even at the edges, unlike agate), its extreme hardness (cannot be scratched by a steel knife), and its smooth, waxy feel when polished. Commonly found in riverbeds, deserts, and coastal areas.