RARE 7″ Gravesia gravesiensis Fossil Ammonite Middle Kimmeridgian Jurassic France – Genuine Collector Specimen with COA

Description

Exceptional Gravesia gravesiensis from the Middle Kimmeridgian

This 7-inch Gravesia gravesiensis fossil ammonite is an outstanding example from the Middle Kimmeridgian stage of the Late Jurassic period, sourced from the renowned fossil beds near Bar-sur-Aube, France. With its distinctive morphology, exceptional preservation, and fine geological provenance, this specimen offers both aesthetic appeal and scientific value. The ammonite pictured is the exact one you will receive, carefully selected for its quality and authenticity.

Geological Age & Provenance

The Middle Kimmeridgian stage, dating to approximately 154–152 million years ago, represents a time when much of Europe was covered by shallow, warm epicontinental seas. These marine environments provided ideal conditions for the preservation of ammonites and other marine fauna. The Bar-sur-Aube region in north-eastern France is a classic locality for Late Jurassic fossils, particularly Kimmeridgian ammonites. Its sedimentary layers preserve a rich record of life in these ancient seas, with fine-grained deposits that often retain exceptional shell detail.

Species Profile & Scientific Classification

Gravesia gravesiensis belongs to the family Gravesiidae, superfamily Perisphinctoidea, and order Ammonitida. This species is known for its moderately involute coiling, well-defined ribbing, and often slightly compressed whorls. The ribs typically bifurcate towards the outer whorl, giving the shell a balanced, ornamental appearance. As a member of Gravesiidae, it is closely associated with the Kimmeridgian faunal assemblages and plays an important role in biostratigraphic zonation of Jurassic sediments in Europe.

Morphological Features

This specimen exhibits all the hallmark traits of Gravesia gravesiensis:

• Strong, evenly spaced ribs extending from the umbilicus to the venter.
• Slightly compressed shell profile, enhancing the rib definition.
• Clean suture lines, a characteristic of well-preserved Jurassic ammonites.
• Natural calcite preservation, replacing the original aragonite while retaining fine detail.

The symmetry and preservation of this example make it ideal for display, while also holding significant value for comparative study alongside related Kimmeridgian ammonite species.

Depositional Environment

During the Middle Kimmeridgian, the area that is now Bar-sur-Aube lay beneath a shallow sea connected to the Tethys Ocean. Sedimentation occurred in calm marine conditions, with fine carbonate muds and silts gradually burying the remains of marine organisms. This low-energy depositional environment promoted the fossilisation of delicate shell structures, resulting in the remarkable preservation seen in this specimen.

Collector Significance

Fossils from Bar-sur-Aube are highly regarded in both academic and private collections due to their clear stratigraphic context and well-preserved features. This 7-inch Gravesia gravesiensis stands out for:

• Size and completeness, providing strong display presence.
• Scientific relevance as an index species for the Middle Kimmeridgian.
• Provenance from a renowned Jurassic locality with a rich fossil record.

Authenticity & Presentation

All of our fossils are 100% genuine specimens and come with a Certificate of Authenticity. This ammonite has been expertly prepared to highlight its natural form and detail, ensuring it is ready for display straight out of the box. Its size, preservation, and origin make it an exceptional addition to any fossil collection, from dedicated enthusiasts to academic researchers seeking a prime example of Gravesia gravesiensis from the Jurassic seas of France.