sedimentary

Green Chert

Microcrystalline Quartz (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 on Mohs scale; Color: Sage green to olive; Luster: Waxy to dull; Crystal structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.6-2.7

Hardness: 6
Color: Sage green to olive
Luster: Waxy to dull

Identified May 14, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 on Mohs scale; Color: Sage green to olive; Luster: Waxy to dull; Crystal structure: Cryptocrystalline; Cleavage: None (conchoidal fracture); Specific gravity: 2.6-2.7

Formation & geological history

Formed through the accumulation of silica-rich organic remains or chemical precipitation in marine environments. Often found as nodules in limestone or as bedded deposits.

Uses & applications

Historically used for stone tools and arrowheads due to its sharp edges; currently used for decorative stone, landscaping, and lapidary purposes.

Geological facts

Green chert is sometimes called 'green jasper.' It is extremely durable and has been used by humans for hundreds of thousands of years to create cutting tools.

Field identification & locations

Identify by its waxy texture, shell-like (conchoidal) fracture pattern, and the fact that it can scratch glass. Common in riverbeds and mountainous regions with ancient seabed deposits.