Sigaloceras calloviense Ammonite Fossil Jurassic Yorkshire UK Genuine Authentic COA

Description

Authentic Jurassic Fossil from Yorkshire, UK

This Sigaloceras calloviense ammonite fossil is a genuine specimen from the Lower Callovian stage of the Middle Jurassic, discovered near South Newbold, Yorkshire, United Kingdom. Carefully selected for its scientific importance and preservation, this ammonite is both a fascinating collector’s item and an outstanding representation of Jurassic marine life. The photographs show the actual specimen you will receive, with a 1 cm scale cube included for size reference. Every specimen is accompanied by a Certificate of Authenticity, confirming it is 100% genuine.

Geological Age and Provenance

The specimen dates to the Lower Callovian stage of the Jurassic Period, approximately 166–163 million years ago. At that time, Yorkshire was submerged beneath warm, shallow epicontinental seas that formed part of the northern reaches of the Tethys Ocean. Sediments of clay, limestone, and marl accumulated across the sea floor, creating excellent conditions for fossilisation. The fossiliferous deposits of Yorkshire are world-renowned, producing ammonites, belemnites, and marine reptiles that provide valuable insights into Jurassic ecosystems.

Species Identification and Classification

Sigaloceras calloviense belongs to the class Cephalopoda, order Ammonitida, superfamily Stephanoceratoidea, and family Cardioceratidae. The genus Sigaloceras is a key ammonite group of the Callovian, distinguished by its strong ribbing and robust shell form. The species calloviense is a classic ammonite used to define a well-known ammonite biozone within the Lower Callovian. Its importance as a zonal fossil has made it one of the most studied species from this time interval, and its presence provides crucial information for correlating Jurassic rock strata across Europe.

Morphology and Distinctive Traits

This specimen exhibits the diagnostic features of Sigaloceras calloviense. The shell is involute, with outer whorls covering much of the inner coils, and its ribbing is strong, bold, and continuous across the flanks, converging toward the venter. The ribs are evenly spaced, giving the shell a striking ornamentation that makes the fossil both visually attractive and easy to identify. This strong ribbing reflects adaptations for shell strength and hydrodynamics within its shallow marine environment. The overall form is both scientifically informative and aesthetically impressive.

Scientific and Stratigraphic Importance

Sigaloceras calloviense is of great stratigraphic significance, serving as an index fossil for the calloviense biozone of the Lower Callovian. Its restricted stratigraphic range, combined with its distinctive morphology, allows geologists to establish precise correlations between marine rock layers across broad regions. Ammonites such as this are essential tools in constructing the Jurassic timescale and in understanding evolutionary patterns within cephalopods. For collectors, this species combines rarity, scientific value, and aesthetic appeal.

Condition and Presentation

This ammonite has been professionally prepared to reveal its natural features, with ribbing, whorl structure, and shell form clearly preserved. The photographs provided are of the actual specimen, ensuring complete transparency and confidence in your purchase. This is a unique, one-of-a-kind specimen and not a cast or reproduction. Its excellent preservation makes it suitable both for display and as a scientifically valuable reference piece.

Guarantee of Authenticity

All of our fossils are 100% genuine, responsibly sourced, and scientifically identified. Each specimen is supplied with a Certificate of Authenticity. This Sigaloceras calloviense ammonite fossil from South Newbold, Yorkshire, is a rare and scientifically significant piece of natural history, making it an outstanding addition for fossil collectors, educational institutions, and natural history enthusiasts.