sedimentary
Pyritized Ammonite
Ammonitida (replaced by Iron Disulfide, FeS2)
AI-generated identification · may be incorrectHardness: 6-6.5 (Mohs scale), Color: Brass-yellow or gold, Luster: Metallic, Crystal Structure: Isometric (replacement of organic spiral structure), Specific Gravity: 4.8-5.0
- Hardness
- 6-6
Identified More sedimentary →
Explore Pyritized Ammonite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-6.5 (Mohs scale), Color: Brass-yellow or gold, Luster: Metallic, Crystal Structure: Isometric (replacement of organic spiral structure), Specific Gravity: 4.8-5.0
Formation & geological history
Formed during the Jurassic or Cretaceous periods in oxygen-poor marine environments where bacteria produced hydrogen sulfide that reacted with iron to replace the shell with pyrite.
Uses & applications
Highly valued for fossil collections, decorative display, and metaphysical jewelry.
Geological facts
Ammonites are extinct cephalopods related to modern squids and octopuses. Pyritization occurs only under very specific chemical conditions in the ocean floor sediment.
Field identification & locations
Identified by its distinctive spiral shape and metallic gold sheen. Commonly found in locations like the Jurassic Coast of England or the Volga River in Russia.
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