Charmouth Ammonite Impression Fossil Jurassic Lyme Regis Dorset UK Lower Lias Black Ven Marls

Description

Genuine Charmouth Ammonite Impression from the Jurassic Coast

Offered here is a genuine Charmouth ammonite impression fossil from the celebrated Black Ven Marls, Black Ven, Lyme Regis, Dorset, on England’s world-famous Jurassic Coast. This specimen preserves a natural impression of an ammonite shell within the surrounding matrix, capturing fine external detail formed during burial and compaction. The photographs show the exact fossil you will receive, carefully selected for clarity, integrity, and visual appeal. Full sizing details are shown in the photos for accurate reference.

All of our fossils are 100% genuine specimens and are supplied with a Certificate of Authenticity, ensuring complete confidence in provenance.

Geological Formation and Age

This fossil originates from the Lower Lias Group, deposited during the Early Jurassic Period, approximately 199–191 million years ago, within the Sinemurian Stage. The Black Ven Marls are composed of fine marine mudstones and marls laid down in a shallow epicontinental sea that covered southern Britain at the time. This formation is internationally important for its abundance of ammonites and its role in defining Early Jurassic stratigraphy. Continuous coastal erosion at Black Ven exposes fresh material, making this locality one of the most significant and productive fossil sites in Europe.

Fossil Type and Nature of Preservation

This specimen is an ammonite impression, where the original aragonitic shell dissolved during burial and early diagenesis, leaving a detailed negative mould preserved within the sediment. Such impressions faithfully record the outer shell morphology, including whorl shape and ribbing, offering valuable insight into ammonite form and growth. Charmouth-area ammonite impressions are highly sought after for their clean definition and natural aesthetic, representing a classic style of preservation from the Lower Lias.

Morphology and Visible Features

The impression displays the characteristic planispiral coiling typical of ammonites, with clearly defined whorls and visible ribbing impressed into the matrix. The rib patterns curve across the flanks, reflecting the hydrodynamic shell form that allowed ammonites to thrive as active nektonic predators in Jurassic seas. The surrounding marl provides strong contrast, enhancing the visibility of the fossil impression and making it especially suitable for display and study.

Depositional Environment

During the Early Jurassic, the Lyme Regis and Charmouth coastline lay beneath a warm, shallow marine environment with relatively calm conditions. Fine sediments settled slowly onto the seabed, allowing shells to be buried before significant disturbance. Periodic low-oxygen conditions limited scavenging and bioturbation, contributing to the preservation of delicate impressions such as this one. These environmental conditions underpin the exceptional fossil record preserved within the Black Ven Marls and the wider Jurassic Coast.

Collecting, Display, and Educational Value

This Charmouth ammonite impression fossil is ideal for private collections, educational settings, museum displays, or refined interior presentation. Its classic British provenance, clear geological context, and natural impression preservation make it both scientifically meaningful and visually engaging. Ammonite impressions from Lyme Regis have long been prized by collectors and have played a key role in the history of palaeontology. Each specimen we offer is individually selected, ensuring you receive an authentic and carefully curated piece of Early Jurassic marine history from one of the world’s most important fossil localities.