Promicroceras Calcite Ammonite Fossil Jurassic Coast Black Ven Charmouth Dorset UK

Description

Specimen Overview

This listing presents a genuine Promicroceras calcite ammonite fossil recovered from the celebrated Black Ven Marls at Charmouth, near Lyme Regis, Dorset. The specimen has been carefully selected for its clarity of preservation, natural presentation, and strong visual contrast between the pale calcite-replaced shell and the darker marl matrix. The photographs show the exact fossil you will receive, with full sizing details clearly visible in the images. As with all of our fossils, this specimen is 100% genuine and is supplied with a Certificate of Authenticity.

Geological Formation & Locality

The fossil originates from Black Ven, one of the most important and productive fossil sites on the Jurassic Coast, a UNESCO World Heritage Site renowned worldwide for its geological significance. The fossil-bearing strata belong to the Lower Lias Group, deposited during the Early Jurassic Period, approximately 199–196 million years ago. The Black Ven Marls consist of fine-grained marine mudstones laid down in a relatively low-energy offshore environment. These calm seabed conditions allowed ammonite shells to be rapidly buried, protecting them from erosion and enabling the excellent preservation seen in fossils from this locality.

Fossil Type & Taxonomy

Promicroceras is an extinct genus of ammonite belonging to the Class Cephalopoda, Subclass Ammonoidea, within the Order Ammonitida. Ammonites were free-swimming marine molluscs related to modern squid and cuttlefish, occupying an important role as predators in Jurassic seas. Promicroceras is particularly characteristic of the earliest Jurassic ammonite faunas and is widely recognised as an important index fossil within the Lower Lias, making it valuable for both scientific study and stratigraphic correlation.

Morphology & Preservation

This Promicroceras specimen displays the classic coiled shell morphology of the genus, with clearly defined whorls and visible growth features that record the animal’s development during life. Calcite replacement has preserved the original shell geometry while enhancing surface detail, giving the fossil a subtle crystalline appearance when viewed under light. Fine curvature and shell form are well expressed, and the surrounding marl matrix remains intact, preserving the ammonite in its original geological context rather than as a detached shell.

Scientific & Collecting Significance

Ammonites from Charmouth and Lyme Regis have been collected and studied for over two centuries and were instrumental in the early development of geological and stratigraphic science. Promicroceras is especially significant due to its role in defining Early Jurassic ammonite successions and understanding post-Triassic marine recovery. Fossils from Black Ven are internationally recognised for their reliable provenance and scientific credibility, making them highly desirable to collectors, educators, and display collections alike.

Display, Care & Authenticity

This fossil is ideal for display in a private collection, educational environment, or natural history cabinet. The specimen has been carefully cleaned to reveal its natural features, with no artificial restoration or reconstruction applied. It remains exactly as preserved by nature. You will receive the exact specimen shown, accompanied by a Certificate of Authenticity, confirming its origin and genuine status.

A classic example of Early Jurassic marine life from one of Britain’s most famous fossil cliffs, this Promicroceras calcite ammonite fossil represents an authentic and scientifically meaningful piece of the Jurassic Coast’s natural history.