Promicroceras Calcite Ammonite Fossil – Black Ven Marls – Lower Jurassic – Charmouth Lyme Regis UK – Genuine with Certificate

Description A superb example of Promicroceras, this calcite-filled ammonite fossil comes from the renowned Black Ven Marls within the Lower Lias along the spectacular Jurassic Coast at Stonebarrow Cliff, Charmouth, Lyme Regis, Dorset, UK. Discovered by our expert team members Alister and Alison on 26 April 2025, this stunning piece has been expertly cleaned, prepped and treated by Alison herself. It is a genuine specimen, and the photograph shows the exact fossil you will receive. Promicroceras is one of the most recognisable genera of Early Jurassic ammonites, notable for its small, involute whorls, narrow ribs, and beautifully preserved calcite infills. This specimen represents the Sinemurian Stage and is a key fossil for dating rocks from this time. These ammonites thrived in low-energy marine environments, where rapid burial in soft sediment led to their exquisite preservation. The calcite infill occurred during diagenesis, giving the fossil a shimmering internal structure highly prized by collectors. Geological & Taxonomic Information: Species: Promicroceras sp. Fossil Type: Ammonite (Calcite-filled) Geological Period: Jurassic Stage: Sinemurian (Lower Jurassic) Formation: Black Ven Marls, Lower Lias Location: Stonebarrow Cliff, Charmouth, Lyme Regis, Dorset, UK Depositional Environment: Shallow marine shelf Family: Oxynoticeratidae Superfamily: Psiloceratoidea Order: Ammonitida What You Receive: The actual fossil specimen photographed A Certificate of Authenticity Professionally packed and shipped with care This piece is an ideal acquisition for fossil collectors, educational institutions, or anyone inspired by Earth’s prehistoric oceans. Note: All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity. Scale cube = 1cm. Please refer to the photograph for full dimensions.