Cretaceous Fossil Sponge Dorset UK White Nothe Chalk Marine Specimen Genuine

Overview & Authenticity

Offered here is a genuine Cretaceous fossil sponge collected from the renowned Grey Chalk Subgroup at White Nothe, Ringstead Bay, Dorset, UK. This is a carefully chosen British marine fossil specimen, selected for its preservation quality, natural structure, and strong collector appeal. The photographs show the actual fossil you will receive, ensuring complete transparency and confidence at the point of purchase.
Every specimen is supplied with a Certificate of Authenticity, including a lifetime guarantee of genuineness, provided on a generic authenticity card.

This particular fossil was personally discovered by our own experienced team members Alister and Alison on 18 January 2024, and has been professionally cleaned, prepared, and treated by Alison, ensuring the specimen is stabilised and ready for long-term display or study.

Geological Setting – Grey Chalk Subgroup, White Nothe

White Nothe is one of Dorset’s most spectacular coastal headlands and forms part of the famous Jurassic Coast World Heritage Site. Although the region is celebrated for Jurassic strata, White Nothe also exposes beautiful Cretaceous chalk deposits rich in marine fossils.
The Grey Chalk Subgroup was deposited approximately 100–94 million years ago during the early Late Cretaceous, when southern Britain lay beneath a warm, shallow sea teeming with marine life. Chalk formed through the slow accumulation of microscopic planktonic algae, creating a soft carbonate seafloor ideal for fossil preservation.

Fossil Type & Biological Origin

Sponges are among the oldest known animal groups, belonging to the phylum Porifera. These simple but highly successful marine organisms thrived in Cretaceous seas, filtering vast amounts of seawater for nutrients and forming an essential part of ancient marine ecosystems.
Fossil sponges are particularly valued for their unusual forms and their importance in understanding prehistoric reef and carbonate shelf environments. Many chalk sponges possessed firm skeletal frameworks that allowed them to fossilise in strong three-dimensional detail.

Morphology & Notable Features

This specimen preserves the distinctive body structure of a marine sponge, often showing an irregular but coherent form shaped by its original filtering architecture. Surface texture may reveal subtle pore patterns, natural sculpturing, and growth features characteristic of chalk sponge fossils.
The pale chalk matrix provides attractive contrast, highlighting the fossil’s shape and making it a striking display specimen. Alison’s preparation work has carefully exposed the fossil while preserving its integrity and natural appearance.

Depositional Environment & Fossilisation

During the Late Cretaceous, White Nothe was part of a calm, shallow marine shelf with clear waters and minimal sediment disturbance. Sponges lived attached to the seabed, forming part of diverse marine communities alongside echinoids, molluscs, and other invertebrates.
After death, sponge remains were gently buried by fine carbonate mud. Over millions of years, mineral replacement and lithification transformed the organism into stone while preserving its external form. Chalk environments are especially important for preserving such delicate marine fossils due to their low-energy depositional conditions.

Collecting & Display Value

British chalk fossils from Dorset are highly sought after for their scientific significance, exceptional provenance, and aesthetic appeal. A fossil sponge from White Nothe represents a remarkable piece of Cretaceous marine history and a tangible connection to the seas that covered Britain during the age of dinosaurs.
Full sizing details are provided in the photographs. As a team-collected, expertly prepared specimen supplied with a Certificate of Authenticity and lifetime guarantee, this fossil sponge is ideal for collectors, educational use, or museum-style display.