sedimentary

Jasper Beach Pebble

Silicon Dioxide (SiO2) - Macro-crystalline Quartz

Hardness: 6.5–7 on Mohs scale; Color: Brownish-yellow, tan, and ocher; Luster: Dull to waxy; Crystal Structure: Trigonal/Microcrystalline; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.58–2.91

Hardness: 6
Color: Brownish-yellow, tan, and ocher
Luster: Dull to waxy

Identified March 21, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the infiltration of silica-rich fluids into volcanic ash or fine-grained sediments during the cooling of the earth's crust. It takes on its rounded, smooth shape through river or ocean wave erosion over thousands of years.

Uses & applications

Used in the lapidary arts for making cabochons and tumbled stones; also common in landscaping, aquarium decor, and pocket stones for meditation or collecting.

Geological facts

Jasper is an impure variety of silica. The name comes from the Old French 'jaspre', meaning 'spotted or speckled stone'. It is distinguished from chalcedony by its opacity, caused by mineral inclusions like iron or clay.

Field identification & locations

Identify in the field by its smooth, water-worn texture and opaque appearance (light does not pass through it). Often found on gravel beaches or in dry riverbeds; this specimen shows characteristic concentric banding or weathering patterns.

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