Rare Iridescent Cardioceras lahuensi Fossil Ammonite Oxfordian Jurassic Volga Russia

Description

Rare Iridescent Cardioceras lahuensi Ammonite Fossil

This listing presents a rare iridescent ammonite fossil, Cardioceras lahuensi, from the Mariae Zone of the Oxfordian Stage, Jurassic Period, discovered at the Dubrovsky Mine in the Saratov District, Volga Region, Russia. Dating back approximately 163–157 million years, this ammonite combines outstanding preservation with a natural shimmering iridescence that makes it highly sought-after among collectors. The specimen shown in the photographs is the exact one you will receive, and it comes complete with a Certificate of Authenticity.

Geological Background

The Oxfordian Stage, forming the earliest part of the Upper Jurassic, was a time of immense marine diversity across Europe and beyond. The Volga region of Russia is one of the most important fossil-bearing localities of this stage, especially known for its beautifully preserved ammonites with pearlescent or iridescent shells. These deposits represent a marine environment along the northern margin of the ancient Tethys Ocean, where fine sedimentation preserved delicate shell structures in exquisite detail.

Within the Oxfordian succession, the Mariae Zone is a significant ammonite biozone. Fossils such as Cardioceras lahuensi are invaluable to palaeontologists for stratigraphic correlation, helping to align rock sequences from Russia with those of Western Europe and beyond.

Scientific Classification

• Species: Cardioceras lahuensi
• Genus: Cardioceras
• Family: Cardioceratidae
• Superfamily: Stephanoceratoidea
• Order: Ammonitida
• Class: Cephalopoda
• Geological Stage: Oxfordian, Jurassic (~163–157 million years ago)
• Zone: Mariae Zone
• Locality: Dubrovsky Mine, Saratov District, Volga Region, Russia

Morphological Features

Cardioceras lahuensi is recognised for its evolute shell structure with pronounced ribbing that extends strongly across its whorls. The ribs often bifurcate, creating an intricate surface pattern. The overall morphology is highly diagnostic, making this ammonite particularly important for identification within its zone.

What makes this specimen truly exceptional is its natural iridescence. The nacreous layers of the shell have mineralised in such a way that they reflect light in brilliant metallic hues. This rainbow-like play of colours is a rare phenomenon in ammonite preservation and greatly enhances both its aesthetic and collector’s value.

Stratigraphic and Palaeontological Importance

Ammonites of the genus Cardioceras are crucial index fossils for the Oxfordian Stage, and C. lahuensi is particularly tied to the Mariae Zone. The presence of this species allows geologists to precisely correlate layers within the Oxfordian and to build a clearer picture of marine faunal succession across Eurasia. Specimens from the Volga region, with their exceptional preservation and iridescence, are highly regarded in palaeontological study as well as in private collections.

Depositional Environment

The Volga ammonites were deposited in calm, shallow marine environments, where fine sediments slowly buried shells, protecting them from physical damage. The geochemical conditions of the Saratov district deposits promoted the preservation of aragonitic shell material, resulting in the rare pearlescent sheen that is still visible today. These conditions make the Volga region one of the few places in the world where iridescent Jurassic ammonites can be found.

Collector and Display Appeal

This rare iridescent Cardioceras lahuensi ammonite represents a striking blend of science, history, and natural beauty. The fossil is not only a scientific specimen that provides valuable insight into Jurassic marine ecosystems but also an aesthetic display piece with its natural rainbow shimmer.

• Type: Rare Iridescent Fossil Ammonite – Cardioceras lahuensi
• Age: Oxfordian, Jurassic (~163–157 million years ago)
• Zone: Mariae Zone
• Location: Dubrovsky Mine, Saratov District, Volga Region, Russia
• Scale: Rule squares/cube = 1 cm (see photographs for sizing)
• Authenticity: 100% genuine specimen with Certificate of Authenticity
• Guarantee: The exact specimen pictured is the one you will receive

This is a unique opportunity to acquire an ammonite that combines scientific significance, rarity, and natural iridescent beauty. A superb specimen for collectors, educators, and enthusiasts of Jurassic fossils and natural history.