Belemnite Fossil Phragmocone Jurassic Whitby UK Genuine Specimen Certificate Authentic

Description

Authentic Jurassic Fossil – Belemnite Phragmocone

This listing is for a genuine Fossil Belemnite Phragmocone, collected from the world-famous fossil beds of Runswick Bay, Whitby, United Kingdom. Dating back to the Middle Lias (Lower Jurassic), around 180 million years ago, this specimen represents the internal chambered part of the belemnite shell, preserved in fine detail. Carefully chosen for its quality and clarity, this fossil offers both scientific interest and aesthetic appeal. Every specimen is individually photographed and supplied with a Certificate of Authenticity, ensuring you receive the exact fossil shown.

Geological Age and Provenance

This belemnite phragmocone comes from the Jurassic Period, specifically the Middle Lias, Lower Jurassic, within the Pliensbachian stage. The Whitby and Runswick Bay coastline is world-renowned for its fossiliferous shales, which preserve a wide variety of marine life, including ammonites, reptiles, bivalves, and belemnites. These deposits were laid down in shallow marine environments where fine sediments buried marine organisms quickly, allowing for excellent preservation. Fossils from Whitby are internationally recognised for their scientific value and are highly sought after by collectors.

Fossil Type and Classification

Belemnites were extinct marine cephalopods, closely related to modern squid and cuttlefish. Unlike ammonites, which had external coiled shells, belemnites had internal skeletons. The phragmocone was the chambered, conical portion of the internal shell, used to control buoyancy as the animal swam through Jurassic seas. In life, the phragmocone would have been encased within a solid guard (rostrum), which is more commonly found in the fossil record. The preservation of the phragmocone is less common, making specimens like this especially desirable to collectors.

Taxonomic details:

• Phylum: Mollusca
• Class: Cephalopoda
• Order: Belemnitida
• Superfamily: Belemnitoidea

Morphology and Distinctive Features

This fossil phragmocone shows several key features typical of belemnite anatomy:

• A conical, chambered internal shell, divided by septa.
• Straight tapering form, in contrast to the coiled shells of ammonites.
• Evidence of chamber divisions that reveal its function in buoyancy regulation.
• Fine preservation within Jurassic shale from Runswick Bay.

Such fossils are particularly important for illustrating the anatomical complexity of belemnites and their evolutionary adaptations as efficient marine predators.

Scientific and Stratigraphic Importance

Belemnites are important index fossils for the Jurassic and Cretaceous, and specific genera are used to identify biozones within these periods. In the Whitby area, belemnites are often found in association with ammonites, providing additional data for stratigraphic correlation. The presence of a phragmocone is significant because it shows the internal structure of the animal rather than just the solid rostrum, offering insights into its mode of life.

Depositional Environment

During the Early Jurassic, Whitby and Runswick Bay were submerged beneath a shallow epicontinental sea. Fine silts and clays accumulated on the seabed, rapidly burying marine organisms after death. In low-oxygen conditions, decay was slowed, allowing mineralisation to preserve fine structural details. This environment produced some of the world’s finest examples of belemnites, ammonites, and marine reptiles, making Whitby one of the most famous fossil localities globally.

Historical and Collecting Significance

Whitby fossils have been collected for centuries, with belemnites often referred to in folklore as “thunderbolts” or “devil’s fingers.” While the solid rostra are commonly found, intact phragmocones are rarer, making this piece a fascinating addition to any fossil collection. Its historical and scientific value lies in its ability to demonstrate the lesser-seen internal anatomy of these iconic Jurassic cephalopods.

Authenticity and Presentation

• 100% Genuine Fossil Specimen
• Type: Belemnite phragmocone
• Age: Jurassic, Middle Lias, approx. 180 million years old
• Location: Runswick Bay, Whitby, United Kingdom
• Supplied with a Certificate of Authenticity
• Scale cube in photographs = 1 cm for accurate sizing
• The fossil shown in the photographs is the exact specimen you will receive

This carefully selected belemnite phragmocone is a rare and scientifically significant fossil from Whitby’s Jurassic coast. A superb addition to any collection, it captures both the beauty and complexity of life in Britain’s ancient seas.