RARE Amaltheus margaritatus Ammonite Fossil – Jurassic Eype UK, Upper Pliensbachian Collector Piece

Description

An extremely rare and finely preserved specimen of Amaltheus margaritatus, discovered in the Upper Pliensbachian Stage of the Jurassic Period, from Eype on the renowned Jurassic Coast of Dorset, United Kingdom. This outstanding fossil was found by our experienced fossil team members Alister and Alison on 19 July 2024, and was meticulously cleaned, prepped, and stabilised by Alison.

Amaltheus margaritatus is an iconic ammonite species, widely known for its fine ribbing and elegant, involute coiling. It is an important index fossil used to define the Margaritatus Zone of the Upper Pliensbachian. Specimens of this quality are uncommon and highly prized among collectors.

Fossil Type: Ammonite (extinct marine cephalopod)

Species: Amaltheus margaritatus

Geological Age: Lower Jurassic – Upper Pliensbachian, Margaritatus Zone

Formation: Charmouth Mudstone Formation (Pliensbachian-aged beds)

Depositional Environment: Formed in a calm offshore marine setting where fine clay and silt particles accumulated over millions of years. Low-oxygen conditions contributed to the exceptional preservation of marine invertebrates, especially ammonites.

Morphological Features:

• Involute shell with fine, dense ribbing
• Narrow umbilicus
• Rounded venter and graceful whorl profile
• Characteristic of the Amaltheidae family

Notable:

• Rare index ammonite from the Margaritatus Biozone
• Excellent detail and preservation
• Discovered and prepared by our in-house team
• The exact specimen in the photograph is the one for sale

Authenticity: All of our fossils are 100% genuine natural specimens and come with a Certificate of Authenticity. The photo includes a 1cm scale cube – please consult for accurate sizing.

This Amaltheus margaritatus ammonite from Eype is a highly collectable fossil with outstanding scientific and aesthetic value—offering a direct connection to the marine life of the Early Jurassic seas.