RARE Iridescent Phylloceras Fossil Ammonite | Cretaceous | Madagascar | Genuine with COA

Description

RARE: Iridescent Phylloceras Fossil Ammonite

Geological Age: Early Cretaceous (~145 to 100.5 million years ago)

Location Found: Madagascar

Fossil Type: Ammonite (Extinct Marine Cephalopod)

Genus: Phylloceras

Order: Ammonitida

Superfamily: Phylloceratoidea

Family: Phylloceratidae

 

Specimen Overview:

This beautiful fossil specimen is an iridescent Phylloceras ammonite, featuring naturally preserved, shimmering shell layers. Found in the Cretaceous marine deposits of Madagascar, this piece showcases the iconic rainbow-like nacre of aragonite, which is highly sought after by collectors and admired for its natural beauty.

The fossil in the photo is the exact specimen you will receive. A 1cm scale rule cube is shown for reference. Please refer to the image for full sizing and preservation detail.

 

Geological Context & Depositional Environment:

During the Cretaceous, Madagascar was positioned along the tropical southern margins of the Tethys Ocean. Shallow marine conditions allowed for abundant life and ideal fossilisation. The calcareous mudstones and limestones in this region enabled the delicate nacreous shell of Phylloceras to fossilise with exceptional preservation, sometimes retaining its original aragonite layers.

These deposits are part of a globally significant fossil record and contain many important ammonite species, particularly from the Albian and Aptian stages.

 

Morphology & Notable Features:

Phylloceras is known for its smooth, involute shell with tightly coiled whorls, a small umbilicus, and almost absent ribbing. Instead, its beauty lies in the subtle growth lines and the iridescent nacre, which creates a rainbow effect under light due to the preserved aragonite. This specimen features excellent iridescence across the shell surface—a rare and naturally occurring phenomenon.

The genus Phylloceras is also significant in ammonite evolution as one of the more primitive forms, giving rise to many later groups.

 

Authenticity & Guarantee:

All of our fossils are 100% genuine specimens and come with a Certificate of Authenticity. Each piece is carefully selected and professionally prepared to ensure both scientific value and stunning visual appeal.

 

Perfect For:

• Fossil and ammonite collectors
• Lovers of natural iridescence and mineral beauty
• Educational and geological collections
• Unique gift or interior décor piece

Add a shimmering jewel of the ancient seas to your collection with this rare iridescent Phylloceras ammonite fossil from Madagascar—a timeless piece of Cretaceous natural history.