sedimentary

Chert / Yellow Jasper

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Yellow to ochre with waxy luster; Crystal Structure: Microcrystalline quartz; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7

Hardness: 6
Color: Yellow to ochre with waxy luster

Identified February 13, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Yellow to ochre with waxy luster; Crystal Structure: Microcrystalline quartz; Cleavage: None (conchoidal fracture); Specific Gravity: 2.6-2.7

Formation & geological history

Formed through the accumulation of silica-rich microfossils or chemical precipitation from hydrothermal fluids in sedimentary basins. The yellow color is due to iron oxide (limonite) inclusions.

Uses & applications

Historically used for stone tools and fire-starting (flint); currently used in jewelry (lapidary), as decorative stones, and in construction aggregate.

Geological facts

Because of its harness and conchoidal fracture, it was the primary material for arrowheads and scrapers in pre-industrial societies. Jasper is often called the 'ultimate nurturer' in metaphysical circles.

Field identification & locations

Identify by its waxy texture and sharp, shell-like (conchoidal) breaking pattern. It will easily scratch glass but cannot be scratched by a steel nail. Commonly found in riverbeds or limestone deposits.