Gryphaea
Fossil
Also called Devil's toenail and Gryphaea arcuata
About it
Oyster with one thick, strongly curled valve and a small flat lid, nicknamed the devil's toenail. Common in Jurassic clays and limestones of England and France, and in Cretaceous beds of Texas.
- Type
- Fossil (mollusc)
- Group
- Bivalve (mollusc)
- Colours
- grey, brown, cream, tan
- Transparency
- opaque
- Periods
- Jurassic, Cretaceous
Typical values: real specimens vary. For more, see mindat.org.