Rare 5″ Stephanoceras perfectum Fossil Ammonite Inferior Oolite Jurassic Coast Burton Bradstock Dorset UK Genuine Specimen with COA

Superb 5″ Stephanoceras perfectum Ammonite from the Inferior Oolite, Jurassic Coast, Dorset, UK

This exceptional 5-inch Stephanoceras perfectum fossil ammonite was discovered by our own team members, Alister and Alison, on 2 October 2025, at Burton Bradstock, Dorset, United Kingdom, along the world-famous Jurassic Coast UNESCO World Heritage Site. The specimen has been expertly cleaned, prepared, and treated by Alison, revealing extraordinary ribbing, sharp detail, and the distinct coiling typical of this species. Found in the Inferior Oolite Formation, this ammonite dates to the Middle Jurassic Period (Bajocian Stage, approximately 170–168 million years ago).

Geological and Depositional Context

The Inferior Oolite Formation represents a sequence of Middle Jurassic limestones deposited in a warm, shallow marine environment that once covered much of southern England. These oolitic limestones and bioclastic sands formed under calm, subtropical seas rich in marine life. Periodic sedimentation and slow burial under carbonate-rich layers allowed for the superb fossil preservation seen in ammonites like Stephanoceras perfectum.
The Burton Bradstock area is part of the Jurassic Coast, an internationally recognised site that exposes nearly 185 million years of Earth’s geological history. The Inferior Oolite at this locality is particularly well known for its Bajocian ammonite faunas, which provide essential data for correlating Jurassic rock formations across Europe. Fossils from this region, preserved in fine-grained oolitic matrix, display exceptional natural definition and form.

Species Overview – Stephanoceras perfectum

Stephanoceras perfectum belongs to the family Stephanoceratidae, superfamily Stephanoceratoidea, order Ammonitida. This species is an iconic representative of the genus Stephanoceras, characterised by its evolute shell, strong radial ribbing, and prominent ventrolateral tubercles. The ribs bifurcate or trifurcate as they cross the flanks, giving the shell a bold, sculpted appearance that defines its aesthetic appeal.
The species name perfectum reflects the fine symmetry and completeness of its whorl structure. Its morphology suggests a fast-swimming, free-floating lifestyle, with a hydrodynamic shell shape designed for mobility and stability in the open Jurassic seas. This ammonite is typically associated with the Garantiana Biozone of the lower Bajocian and serves as a key index fossil for dating and correlating Bajocian strata in western Europe.

Scientific and Historical Significance

Stephanoceras perfectum is a scientifically valuable ammonite for understanding the evolutionary radiation of the Stephanoceratidae during the Middle Jurassic. The Bajocian period marked a phase of rapid diversification among ammonites, and S. perfectum represents one of the most ornate and recognisable forms of this time.
Its presence in the Inferior Oolite provides a snapshot of marine life thriving in stable carbonate shelf environments. Historically, ammonites of this species were among those studied by 19th-century geologists who laid the foundations of British stratigraphy. Specimens from Burton Bradstock are considered premium examples, often prized by both collectors and paleontologists for their completeness and intricate ribbing.

Condition, Provenance, and Authenticity

This is a 100% genuine fossil specimen, professionally discovered, cleaned, and stabilised to reveal maximum natural detail while maintaining scientific integrity. The surface displays crisp ribbing and prominent tubercles that clearly define its Stephanoceras morphology. The fossil has not been artificially enhanced — only carefully prepared by Alison to showcase its full geological and aesthetic beauty.
The photograph shows the exact specimen you will receive, ensuring complete transparency. A Certificate of Authenticity is included with your purchase, verifying the fossil’s identity, age, formation, and provenance.

Details at a Glance

• Species: Stephanoceras perfectum

• Family: Stephanoceratidae

• Superfamily: Stephanoceratoidea

• Order: Ammonitida

• Age: Bajocian Stage, Middle Jurassic (~170–168 million years ago)

• Biozone: Garantiana Biozone

• Formation: Inferior Oolite

• Locality: Burton Bradstock, Dorset, United Kingdom

• Discovered by: Alister and Alison on 02 October 2025

• Prepared by: Alison

• Condition: Genuine, fully prepared specimen; exceptional preservation and display quality

• Scale: Cube = 1 cm (see photo for full sizing)

• Included: Certificate of Authenticity

A Magnificent Collector’s Fossil from the Jurassic Coast

This Stephanoceras perfectum ammonite is an extraordinary example of Britain’s rich Jurassic fossil heritage. With its bold sculptural form, outstanding preservation, and provenance from the renowned Inferior Oolite of Burton Bradstock, this specimen represents both a scientifically important and visually striking addition to any fossil or natural history collection.