A++ Quality Psiloceras planorbis | Jurassic Rainbow Ammonite | North Somerset, England

Species: Psiloceras planorbisAge: Jurassic (180 million years ago)Formation: Blue Lias FormationLocation: North Somerset, England Approx. Size of Ammonite: 2" x 1.75" Approx. Size of Matrix: 7" x 5.5" x 1.25"   This beautiful double Psiloceras planorbis specimen has brilliant rainbow iridescence throughout their shell. These specimens were discovered in the Blue Lias Formation, near North Somerset, England. Blue Lias Formation - A geological formation in many parts of England and parts of South Wales. Part of the Lias group. The formation is a sequence of limestone and shale layers which were formed in the latest Triassic and early Jurassic periods. This formation ages back between 195 and 200 million years ago. Psiloceras - An extinct genus of ammonite. They are one of the earliest known Jurassic ammonites. These ammonites had a smooth shell which set them apart from most other early Jurassic ammonites.