sedimentary
Flint
SiO2 (Microcrystalline Quartz)
AI-generated identification · may be incorrectHardness of 7 on the Mohs scale, typically dark gray or black with a waxy to vitreous luster and conchoidal fracture.
Identified More sedimentary →
Explore Flint in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 7 on the Mohs scale, typically dark gray or black with a waxy to vitreous luster and conchoidal fracture.
Formation & geological history
Formed through the chemical replacement of limestone or chalk by silica-rich groundwater over millions of years.
Uses & applications
Historically used for making stone tools and fire-starting; currently utilized in landscaping and decorative aggregates.
Geological facts
Flint produces sparks when struck against steel due to its high hardness and brittle, sharp conchoidal breakage.
Field identification & locations
Identified easily by its conchoidal fracture, dark coloration, and ability to scratch glass; commonly found in chalk deposits worldwide.
More like this
Other sedimentary specimens
Fossil-bearing concretion, possibly containing a fossil shell or other organic inclusion
Calcareous concretion; exact fossil and host-rock composition are not identifiable from the image
fossil
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Sandstone
Arenite
sedimentary
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary