Ancolioceras opalinoides Ammonite Fossil Jurassic Dorset UK COA Genuine Horn Park Quarry Beaminster Upper Aalenian Collectable

Description

Genuine Ancolioceras opalinoides Ammonite Fossil

This listing is for a genuine Ancolioceras opalinoides ammonite fossil from Horn Park Quarry, Beaminster, Dorset, UK. This carefully chosen fossil dates from the Middle Jurassic, Upper Aalenian, making it an authentic marine cephalopod from one of Britain’s most important Jurassic fossil localities. The photograph shows the actual specimen you will receive, so the fossil’s natural preservation, colour, surface detail, matrix and overall character can be viewed before purchase.

This fossil is supplied with a Certificate of Authenticity lifetime guarantee generic card, giving confidence that the specimen is genuine. Full sizing details can be seen in the photo.

Fossil Type and Species

Ancolioceras opalinoides is an ammonite, belonging to the extinct group of shelled marine cephalopods that lived in ancient seas during the Mesozoic Era. Ammonites are related to modern squid, octopus and cuttlefish, but unlike those living animals, they possessed a coiled external shell divided internally into chambers. The living animal occupied the final body chamber, while earlier chambers helped with buoyancy control as it moved through the water column.

The species name opalinoides reflects its association with the Upper Aalenian ammonite faunas of the Middle Jurassic. Ammonites from this interval are especially valued because they are important guide fossils, helping geologists date and correlate rock layers with remarkable precision. A specimen such as this is therefore both an attractive fossil display piece and a scientifically interesting example of Jurassic marine life.

Geology and Age

This ammonite comes from the Middle Jurassic, Upper Aalenian Stage, approximately around 172 million years old. During this period, the region now known as Dorset was covered by warm, shallow seas. These seas supported a rich and diverse marine ecosystem, including ammonites, belemnites, bivalves, brachiopods, gastropods, crinoids and other invertebrates.

The sediments at Horn Park Quarry are part of the classic Jurassic succession of southwest England, where marine limestones and fossil-bearing beds record changing sea levels, seabed conditions and faunal communities through time. The Aalenian deposits represent an important interval between the Early and Middle Jurassic, preserving ammonites that are highly useful for biostratigraphy and palaeontological study.

Horn Park Quarry, Beaminster, Dorset

Horn Park Quarry near Beaminster in Dorset is a famous British Jurassic fossil locality, particularly known for its Aalenian and Bajocian ammonite assemblages. The quarry has long been recognised by fossil collectors and palaeontologists for its exceptionally interesting ammonite record and its place in the study of Jurassic stratigraphy.

Dorset is world renowned for Jurassic fossils, and specimens from Horn Park Quarry are especially desirable because they come from a well-known and precisely recorded locality. Fossils from this area are popular with collectors who appreciate classic British material, locality-specific specimens and ammonites with strong geological context.

Ammonite Morphology and Display Features

Ammonites such as Ancolioceras opalinoides typically display the classic coiled shell form that makes Jurassic ammonites so recognisable. Depending on preservation, features may include visible whorls, natural ribbing, shell curvature, chamber traces, matrix contrast and surface texture. These details reflect both the original shell structure and the fossilisation process that preserved the ammonite for millions of years.

As a natural fossil, each specimen is unique. Variations in colour, shape, preservation, mineralisation, matrix and surface wear are part of the fossil’s individual character. This makes the piece ideal for collectors who want a distinctive Jurassic ammonite rather than a mass-produced display item.

Collecting Appeal

This Ancolioceras opalinoides ammonite fossil is an excellent choice for collectors of British fossils, Jurassic ammonites, Dorset fossils, Horn Park Quarry fossils, Aalenian ammonites and natural history specimens. It would make a strong addition to a fossil cabinet, educational geology collection, school display, study set or natural history gift.

Its appeal comes from the combination of a named species, a classic British locality, Middle Jurassic age and genuine fossil authenticity. The actual specimen shown in the listing photo is the fossil supplied, allowing the buyer to clearly see the piece before purchase.

Authenticity and Presentation

This is a 100% genuine fossil specimen and includes a Certificate of Authenticity lifetime guarantee generic card. The fossil has been carefully chosen and photographed to show the actual item being offered. Full sizing can be checked from the photo, and the specimen is suitable for display, collection, study or gifting.