Sigloceras Fossil Ammonite from Water Park Cotswolds United Kingdom Middle Oxfordian Jurassic COA

Description

Authentic Sigloceras Fossil Ammonite – Middle Oxfordian, Jurassic

This listing features a genuine Sigloceras fossil ammonite from the Middle Oxfordian Stage of the Jurassic Period, collected from Water Park in the Cotswolds, United Kingdom. This is a carefully chosen specimen, selected for its preservation and visual appeal, and the photographs show the exact fossil you will receive. The specimen originates from the Alice Purnell Collection, adding notable provenance and collector value. As with all our fossils, this ammonite is 100% genuine and is supplied with a Certificate of Authenticity

Geological Setting – Middle Oxfordian, Jurassic Period

The Oxfordian Stage (approximately 163–157 million years ago) represents a key interval within the Late Jurassic, characterised by warm, shallow epicontinental seas that covered much of what is now southern Britain. The Cotswolds lay beneath these tropical marine waters, forming an ideal environment for ammonites to thrive in large numbers.

Sediments deposited during the Middle Oxfordian consist largely of limestones and marls, laid down in relatively calm marine conditions. These sediments provided excellent conditions for the preservation of shelled cephalopods such as Sigloceras. Fossils from this interval are particularly important for biostratigraphy, as ammonites evolved rapidly and are used extensively to date and correlate Jurassic rock layers across Europe.

Fossil Type and Species – Sigloceras

Sigloceras is a well-known Jurassic ammonite genus, valued for its distinctive shell form and stratigraphic importance. Members of this genus are typically characterised by:

• Moderately involute coiling, with inner whorls partially covered
• Compressed whorl section, giving the shell an elegant, streamlined appearance
• Fine, regular ribbing across the flanks
• Distinctive suture patterns, visible on well-preserved specimens
• Hydrodynamic shell morphology, suited to active swimming

These traits reflect a nektonic lifestyle, with Sigloceras inhabiting open marine waters as a fast-moving predator. Its consistent morphology and restricted stratigraphic range make it a reliable index fossil for the Middle Oxfordian.

Water Park, Cotswolds – A Classic British Locality

Water Park in the Cotswolds is a respected Jurassic fossil locality, producing ammonites of excellent quality and scientific interest. The area forms part of the wider Jurassic limestone belt of southern England, long studied by palaeontologists for its well-exposed and fossil-rich strata.

Ammonites recovered from this region are prized by collectors due to their preservation, natural colouration, and clear morphological features. British Oxfordian ammonites, particularly those from established localities such as Water Park, remain highly sought-after worldwide for both private collections and academic reference.

Provenance – Alice Purnell Collection

This specimen originates from the Alice Purnell Collection, adding an extra layer of historical and collector significance. Fossils from established collections are valued not only for their quality but also for their documented provenance, which enhances both their authenticity and desirability.

Your Genuine Fossil Specimen

• Genus: Sigloceras
• Fossil Type: Ammonite
• Geological Age: Middle Oxfordian, Jurassic
• Locality: Water Park, Cotswolds, United Kingdom
• Provenance: Alice Purnell Collection
• Authenticity: 100% genuine with Certificate of Authenticity
• Condition: Carefully selected, well-preserved specimen
• Sizing: Full measurements shown in listing photographs
• Exact Specimen Shown: You will receive the fossil pictured

This Sigloceras ammonite is an excellent addition to any fossil collection, offering a combination of scientific importance, classic British provenance, and timeless natural beauty. It is ideal for collectors, educators, and anyone with an appreciation for the rich Jurassic heritage of the United Kingdom.