Ichthyosaur Fossil Bone Block with Two Vertebrae Jurassic Coast Lyme Regis Dorset UK – Genuine Black Ven Marls Lower Lias Specimen with COA

Description

Authentic Ichthyosaur Fossil Bone Block from the Jurassic Coast, Dorset

This impressive Ichthyosaur Fossil Bone Block originates from the Black Ven Marls of the Lower Lias Formation, part of the Jurassic Coast at Black Ven, Lyme Regis, Dorset, UK. Discovered by our own collectors Alister and Alison on 03 November 2025, this remarkable specimen has been carefully cleaned, prepped, and treated by Alison using professional conservation techniques. The fossil dates to approximately 195–200 million years ago, from the Early Jurassic (Sinemurian) Stage, and contains two well-preserved vertebrae and two additional bone elements, likely ribs or limb fragments, all naturally aligned within the marl matrix. This scientifically significant and visually striking piece represents a rare opportunity to own an authentic section of an ancient marine reptile from Britain’s most famous fossil locality.

Geological and Scientific Context

The Ichthyosaur was a marine reptile belonging to the order Ichthyosauria, a group of swift, dolphin-like predators that dominated the Jurassic seas. Unlike fish, Ichthyosaurs were air-breathing vertebrates with streamlined bodies adapted for life in open water. The Black Ven Marls, part of the Charmouth Mudstone Formation, have yielded some of the world’s most historically important Ichthyosaur finds—many of which were first discovered and described in the early 19th century by the pioneering fossil hunter Mary Anning.

Deposited in a low-energy, shallow marine environment, these marls were laid down in fine layers of mud and calcareous sediment that accumulated under oxygen-poor conditions. Such conditions prevented scavengers and bacterial decay, allowing for exceptional fossil preservation. The sediments of Black Ven are globally recognised for producing articulated marine reptile skeletons, ammonites, and other Jurassic marine life that document one of the richest fossil records of the Early Jurassic period.

Morphology and Distinctive Features

This fossil block contains two articulated Ichthyosaur vertebrae, identifiable by their distinctive biconcave (amphicoelous) shape—concave on both sides—a key diagnostic feature of Ichthyosaur spinal bones. These vertebrae are compact, symmetrical, and display clear articulation surfaces, with surrounding bone texture preserved in fine detail. In addition to the vertebrae, the specimen includes two other bone elements, likely ribs or appendicular bones, offering valuable context to the skeletal anatomy.

The vertebrae would have formed part of the Ichthyosaur’s powerful tail or trunk region, which enabled strong lateral propulsion for fast swimming. Ichthyosaurs were agile predators capable of reaching high speeds in pursuit of fish and belemnites. Their skeletons were lightweight yet strong, featuring hundreds of closely spaced vertebrae that provided flexibility and strength in motion—an evolutionary adaptation similar to that of modern dolphins.

This specimen’s preservation highlights the delicate internal bone structures and fine surface detail, showing natural mineralisation that enhances contrast within the marl matrix. The clarity and positioning of the bones make it both scientifically informative and visually captivating—a fine representation of the exceptional preservation conditions found at Black Ven.

Geological Age and Depositional Environment

Dating to the Sinemurian Stage of the Lower Jurassic, approximately 197 million years ago, the Black Ven Marls record a time when Dorset was submerged beneath a warm, tropical sea. Fine silt and mud accumulated slowly on the sea floor, burying marine reptiles, ammonites, and other fauna. The calm, low-oxygen environment ensured remarkable preservation of even delicate skeletal elements.

This region forms part of the UNESCO World Heritage-listed Jurassic Coast, recognised for its continuous geological record spanning 185 million years of Earth’s history. Fossils like this Ichthyosaur bone block are key to understanding marine ecosystems of the Early Jurassic, offering direct evidence of ancient vertebrate evolution and palaeoecology.

Preparation and Provenance

This specimen was discovered and prepared by our in-house team, ensuring authenticity and exceptional care throughout the entire process. Alison’s skilled preparation has revealed the vertebrae and associated bones in natural alignment, cleaning away matrix material while preserving original mineral surfaces. The fossil has been stabilised for long-term preservation and visual clarity. Every fossil we sell is 100% genuine and comes with a Certificate of Authenticity, confirming its identification, provenance, and geological context.

Our preparation approach maintains both scientific value and aesthetic presentation, making this fossil ideal for collectors, museums, or educational displays. Each piece we prepare carries full provenance from discovery through to completion.

Size and Presentation

Scale cube = 1 cm. Please refer to the photographs for full sizing. The images show the exact specimen you will receive—not a stock image. The vertebrae and bones are naturally embedded within their original marl matrix, which forms a stable and visually pleasing display block. The natural contrast between the grey-brown bone and pale matrix highlights the fine anatomical detail.

This fossil can be displayed flat or upright and is suitable for both scientific study and decorative display. Its impressive preservation and geological authenticity make it a stand-out addition to any fossil collection.

A Rare Collector’s Specimen from the Jurassic Coast

This Ichthyosaur Fossil Bone Block with Two Vertebrae and Two Associated Bones represents a genuine piece of Britain’s Jurassic heritage. Discovered at Black Ven, Lyme Regis, and expertly prepared, it embodies both the scientific and aesthetic qualities that make Dorset’s fossils world-famous—a remarkable testament to life beneath the seas of the Early Jurassic.