sedimentary

Chert / Flint

Chert (Microcrystalline Quartz, SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: ग्रे, भूरा, और काला; Luster: Waxy to dull; Crystal structure: Cryptocrystalline; Cleavage: None (Conchoidal fracture); Specific gravity: 2.65

Hardness: 7 on Mohs scale
Color: ग्रे, भूरा, और काला
Luster: Waxy to dull

Identified May 20, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the accumulation of silica-rich organic remains (like diatoms or radiolaria) or the chemical precipitation of silica from groundwater within sedimentary beds like limestone.

Uses & applications

Historically used for making stone tools (arrowheads); used in construction as an aggregate, road surfacing, and as a sparking element in traditional flintlock mechanisms.

Geological facts

Flint is a variety of chert that occurs in chalk or marly limestone. It produces sparks when struck against steel due to its hardness and silica content.

Field identification & locations

Identify in the field by its very smooth, glass-like curved (conchoidal) fractures and its ability to easily scratch glass. Found globally in sedimentary rock outcrops.