Horn Park Graphoceratid Fossil Ammonite Bajocian Jurassic Dorset UK Genuine Ammonite Specimen from Horn Park with COA

Description

Authentic Horn Park Graphoceratid Fossil Ammonite

This specimen is a beautifully preserved Graphoceratid ammonite fossil from the Bajocian stage of the Middle Jurassic, collected at the world-renowned Horn Park Quarry in Dorset, United Kingdom. With its ribbed shell and distinctive coiling, this ammonite represents a classic example of the marine life that thrived in Britain’s Jurassic seas. The photographs show the actual fossil you will receive, with a 1 cm scale cube and rule squares for accurate sizing. Every fossil is 100% genuine and accompanied by a Certificate of Authenticity.

Geological Context – Bajocian Stage, Horn Park

The Bajocian stage, dating to approximately 170.3–168.3 million years ago, is a subdivision of the Middle Jurassic characterised by abundant and diverse ammonite faunas. The Horn Park Quarry in Dorset is one of the most important fossil localities in Britain and is celebrated for its exceptional Bajocian ammonite assemblages. These fossils were deposited in shallow marine environments during a time when warm seas covered much of southern England. Fine-grained calcareous sediments preserved ammonites in exquisite detail, making Horn Park fossils vital for both collectors and researchers.

Fossil Type – Graphoceratid Ammonites

Graphoceratid ammonites belong to the family Graphoceratidae, within the order Ammonitida and the superfamily Hildoceratoidea. They are characterised by their compressed shells, involute coiling, and well-defined ribbing. These ammonites are of particular stratigraphic importance, as they serve as index fossils for Bajocian biozones, allowing geologists to date Jurassic rocks with precision and correlate sequences across Europe. Their diagnostic morphology makes them easy to recognise and highly valued by palaeontologists.

Morphological Features

This Graphoceratid ammonite displays the classic features of the group. Its involute shell conceals much of the inner whorls, while the flanks are adorned with strong ribs that radiate outward, occasionally bifurcating before crossing the venter. The compressed profile and narrow outer margin are hallmarks of this family. Such features reflect adaptations for active swimming in open marine waters, with streamlined shells suited for life in the Middle Jurassic seas. This specimen preserves these traits clearly, offering both scientific insight and aesthetic appeal.

Scientific and Collectible Importance

Graphoceratid ammonites are significant in Jurassic stratigraphy, particularly in the Bajocian stage, where their distribution defines multiple ammonite zones. Their reliability as zone fossils makes them invaluable for dating and correlating rock strata across regions. For collectors, this specimen represents both a piece of geological history and an attractive fossil with striking ribbing and elegant coiling. Its provenance from Horn Park adds additional value, as this site is one of the most respected and historically significant fossil localities in Britain.

Provenance and Guarantee

Collected from the Horn Park Quarry in Dorset, this ammonite has been carefully chosen for its preservation and clarity of features. It has been professionally handled to ensure authenticity and display quality. As with all our fossils, it comes with a Certificate of Authenticity, guaranteeing that it is a genuine specimen. The fossil shown in the photographs is the exact one you will receive.

A Rare Jurassic Fossil from Dorset

This Graphoceratid ammonite fossil from Horn Park is a superb addition to any fossil collection. With its finely ribbed shell, scientific importance as an index fossil, and provenance from one of Britain’s most significant Jurassic localities, it is both a display-worthy piece and a valuable specimen of natural history.