Double Promicroceras Calcite Ammonite Fossil Jurassic Coast Black Ven Charmouth Dorset UK

Description

Specimen Overview

This impressive fossil specimen features a Double Promicroceras calcite ammonite, preserved together on the same original slab of matrix from the Black Ven Marls, Charmouth, near Lyme Regis, Dorset. The piece displays two Promicroceras ammonites in natural association, offering enhanced scientific and visual interest compared to a single specimen. Pale calcite preservation highlights the shell forms beautifully against the darker marl, clearly defining the ammonites’ coiled structure. The photographs show the exact fossil you will receive, with full sizing details visible in the images. As with all of our fossils, this specimen is 100% genuine and supplied with a Certificate of Authenticity.

Geological Formation & Locality

The fossil originates from Black Ven, one of the most important fossil-producing cliffs on the Jurassic Coast, a UNESCO World Heritage Site. These sediments 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 muds laid down in a relatively low-energy offshore environment. Periodic sedimentation events rapidly buried shells on the seabed, creating ideal conditions for the preservation of ammonites in both three-dimensional and mineral-replaced forms.

Fossil Type & Taxonomy

Promicroceras is a classic Early Jurassic ammonite genus belonging to the Class Cephalopoda, Subclass Ammonoidea, within the Order Ammonitida. Ammonites were extinct marine molluscs related to modern squid and cuttlefish, occupying an important role as active predators in Jurassic seas. Promicroceras is particularly significant within the Lower Lias due to its usefulness as an index fossil, helping to define specific intervals within Early Jurassic marine strata.

Morphology & Preservation

Both ammonites in this specimen display the characteristic tightly coiled shell form of Promicroceras, with clearly defined whorls and visible growth features. Calcite replacement has preserved the original shell geometry while enhancing surface detail and providing a subtle crystalline appearance under light. The surrounding marl matrix remains intact, preserving the fossils in their original geological context rather than as isolated shells. The natural pairing of two ammonites on a single slab makes this a genuine double specimen rather than a composite.

Scientific & Collecting Significance

Ammonites from Charmouth and Lyme Regis have been collected and studied for over two centuries and played a key role in the early development of geological and stratigraphic science. Promicroceras is especially important within Early Jurassic ammonite successions and is widely recognised in both academic and collecting circles. Specimens from Black Ven are internationally valued for their reliable provenance and scientific credibility. A double Promicroceras specimen is less common than single examples and offers increased educational and display value.

Display, Care & Authenticity

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

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