Rare Fossil Heteromorph Hamites attenuatus Uncoiled Ammonite Gault Clay Albian Cretaceous UK COA

Description

Rare Hamites attenuatus Heteromorph Ammonite Fossil from Folkestone, United Kingdom

This exceptional fossil represents a Hamites attenuatus heteromorph ammonite, a remarkable species known for its unusual uncoiled shell structure. Collected from the world-renowned Gault Clay deposits at Folkestone, Kent, United Kingdom, this specimen dates to the Albian Stage of the Early Cretaceous Period, approximately 113–100 million years ago. Unlike the more familiar planispiral ammonites, Hamites is a heteromorph ammonite, meaning its shell deviates from the typical coiled form and instead extends into elongated, partially uncoiled whorls. This distinctive morphology makes it one of the most intriguing ammonites of the Albian seas. The specimen offered here is the exact fossil shown in the photographs, displayed with a 1 cm scale cube for accurate sizing, and comes with a Certificate of Authenticity.

Geological Age and Depositional Environment

The Albian Stage represents the last subdivision of the Early Cretaceous, a period of widespread shallow seas and significant ammonite diversification. The Gault Clay Formation at Folkestone is world-famous for its exquisitely preserved ammonites, belemnites, bivalves, and marine reptiles. Formed under a relatively deep marine depositional environment, the fine-grained clay sediments allowed for exceptional fossil preservation.

The Gault Clay is also of major scientific importance, with ammonite faunas serving as key biostratigraphic markers. Hamites attenuatus is an index species that helps define intervals within the Albian, allowing geologists to date strata with precision across Europe.

Scientific Classification

• Type: Heteromorph Uncoiled Ammonite Fossil
• Genus: Hamites
• Species: attenuatus
• Order: Ammonitida
• Superfamily: Ancyloceratoidea
• Family: Hamitidae
• Age: Albian, Early Cretaceous (~113–100 million years ago)
• Formation: Gault Clay
• Locality: Folkestone, Kent, United Kingdom

Distinctive Morphological Features

The Hamites attenuatus ammonite is instantly recognisable for its unconventional shape:

• Uncoiled, elongated shell with whorls that extend in near-linear or slightly curved forms.
• Fine ribbing running across the flanks, providing structural strength and distinctive ornamentation.
• Tuberculation sometimes present along the ribs or ventral regions.
• Open shell structure that distinguishes it from the more compact planispiral ammonites.

This unusual morphology reflects the heteromorph adaptation, which may have influenced buoyancy and swimming behaviour, making Hamites a fascinating subject of paleontological research.

Paleoecological Importance

Heteromorph ammonites like Hamites attenuatus thrived in the warm Cretaceous seas that covered much of Europe. Unlike tightly coiled ammonites, the uncoiled forms may have been slower swimmers, possibly occupying a more planktic lifestyle, drifting in the water column and feeding on small crustaceans and plankton. Their distinctive morphology highlights the evolutionary experimentation within the Ammonitida during the mid-Cretaceous, when seas were highly productive and diverse.

The Gault Clay provides a unique window into this ecosystem, preserving ammonites alongside a wide variety of marine life. This makes specimens from Folkestone not only visually striking but also scientifically valuable for reconstructing Albian marine environments.

Collector and Display Value

A Hamites attenuatus heteromorph ammonite fossil from the Gault Clay is a rare and desirable specimen for collectors, educators, and enthusiasts alike. Its unusual uncoiled form immediately sets it apart from typical ammonites, making it a conversation piece as well as a scientifically significant fossil. This carefully chosen example captures the evolutionary diversity of ammonites and illustrates the remarkable range of shell morphologies that existed during the Cretaceous.

With its guaranteed authenticity, provenance from Folkestone, and excellent preservation, this specimen offers both aesthetic appeal and scientific interest. It is perfect for display in a personal collection, educational setting, or as a unique natural history piece.

Key Features

• Species: Hamites attenuatus
• Type: Rare heteromorph uncoiled ammonite fossil
• Age: Albian, Early Cretaceous (~113–100 million years ago)
• Location: Gault Clay Formation, Folkestone, United Kingdom
• Notable Traits: Uncoiled elongated shell, fine ribbing, distinctive heteromorph morphology
• Authenticity: Guaranteed genuine specimen with Certificate of Authenticity
• Display: Exact fossil shown, with 1 cm scale cube included

This rare Hamites attenuatus heteromorph ammonite is a striking fossil that combines scientific importance with natural beauty, representing one of the most distinctive ammonite forms of the Cretaceous seas.