Rock Identifier
Chert or Flint (Silicon dioxide (SiO2)) — sedimentary
sedimentary

Chert or Flint

Silicon dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness of 6.5-7 on the Mohs scale, typically gray, brown, or black, with a waxy or dull luster, conchoidal fracture.

Identified More sedimentary
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Physical properties

Hardness of 6.5-7 on the Mohs scale, typically gray, brown, or black, with a waxy or dull luster, conchoidal fracture.

Formation & geological history

Forms as a chemical precipitate or from the accumulation of silica-rich biological remains (like radiolarians or diatoms) in marine environments.

Uses & applications

Historically used for making stone tools (arrowheads, scrapers) due to its conchoidal fracture. Sometimes used as an aggregate in construction.

Geological facts

Flint is a type of chert often found as nodules in chalk or limestone deposits, famous for its use in starting fires.

Field identification & locations

Identify by its hardness (scratches glass), waxy luster, and conchoidal fracture. Found worldwide in sedimentary rock formations.