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, selected for its preservation quality, natural sculptural form, and strong display appeal. The photographs show the actual specimen you will receive, ensuring complete transparency and confidence when purchasing.
Every fossil is supplied with a Certificate of Authenticity, including a lifetime guarantee of genuineness, provided on a generic authenticity card.

This particular specimen 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 fossil is stabilised and ready for long-term collecting or display.

Geological Setting – Grey Chalk Subgroup, White Nothe

White Nothe is one of Dorset’s most striking coastal headlands and forms part of the Jurassic Coast World Heritage Site. While the area is famous for Jurassic fossils, White Nothe also exposes superb Cretaceous chalk deposits rich in marine invertebrates.
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 epicontinental sea. Chalk formed through the gradual accumulation of microscopic carbonate plankton, creating a fine seafloor sediment that preserved marine life with exceptional fidelity.

Fossil Type & Biological Origin

Sponges belong to the phylum Porifera, one of the oldest groups of animals on Earth. In the Late Cretaceous seas of Dorset, sponge communities flourished in clear, well-oxygenated waters, filtering seawater for nutrients and forming an important part of marine carbonate ecosystems.
Fossil sponges are especially valued for their unusual morphology, as their preserved forms often reflect complex growth structures shaped by water flow and seabed conditions.

Morphology & Notable Features

This specimen preserves the characteristic external structure of a marine sponge, often displaying an irregular yet coherent growth form shaped by its original filtering architecture. Surface texture may show subtle pore impressions, natural ridging, or sculptured contours typical of chalk sponge fossils.
The pale grey-white chalk matrix provides attractive contrast, allowing the fossil to stand out clearly. Alison’s careful preparation work has revealed the fossil’s form while maintaining its authenticity and natural integrity.

Depositional Environment & Fossilisation

During the Late Cretaceous, White Nothe lay beneath calm shallow seas with minimal sediment disturbance. Sponges lived attached to the seabed alongside echinoids, bivalves, ammonites, and other marine invertebrates.
After death, sponge remains were gently buried in fine carbonate mud. Over millions of years, mineral replacement and lithification transformed the organism into stone while preserving its three-dimensional external form. Chalk environments are particularly important for preserving 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, provenance, and aesthetic appeal. A fossil sponge from White Nothe represents a tangible piece of Cretaceous marine history and a direct 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 collections, or museum-style display.