sedimentary
Chert Arrowhead (Jasper)
Microcrystalline Quartz (SiO2)
AI-generated identification · may be incorrectHardness: 6.5-7 Mohs; Color: reddish-brown; Luster: waxy to vitreous; Structure: cryptocrystalline; Breakage: conchoidal fracture.
- Hardness
- 6
- Color
- reddish-brown
- Luster
- waxy to vitreous
Identified More sedimentary →
Explore Chert Arrowhead (Jasper) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7 Mohs; Color: reddish-brown; Luster: waxy to vitreous; Structure: cryptocrystalline; Breakage: conchoidal fracture.
Formation & geological history
Formed through the accumulation of silica-rich fluids or organic remains (like radiolarians) in sedimentary environments, later hardening into dense rock. Date back millions of years.
Uses & applications
Historically used for tools and weapons; modernly used for decoration, jewelry, and educational collectibles.
Geological facts
Chert is one of the most durable stones used by ancient civilizations for knapping due to its predictable conchoidal fracturing which creates razor-sharp edges.
Field identification & locations
Identified by its waxy texture, extreme hardness (can scratch glass), and the shell-like curved patterns (conchoidal flakes) left by the knapping process.
More like this
Other sedimentary specimens
Fossiliferous Sedimentary Rock
Sedimentary limestone with invertebrate fossil imprint
fossil
Sandstone or Siltstone
Arenite (if sandstone)
Sedimentary
Quartz pebble
Silicon dioxide (SiO2)
sedimentary
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
sedimentary
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Shale (or Mudstone/Siltstone)
Sedimentary Mudrock (SiO2, Al2O3 base with clay minerals)
sedimentary