A stunning and truly unique example of a crinoid fossil of the species Pentacrinites fossilis from the world-famous Jurassic Coast beach of Charmouth, Dorset UK.
The fossil measures 145 mm (5.75 inches) across, which is large for a crinoid fossil from this location. It consists of lots of crinoid stems from a single colony of animals, all running over the top of one another in a very unusual fashion. It was preserved in a limestone nodule and has been painstakingly prepared out using air abrasive techniques, which is why it is preserved three dimensionally. These crinoids lived in colonies attached to driftwood in the Jurassic oceans and these ones appear to have wrapped around one another before they became fossilised on the seafloor. The stems are preserved in 3D with great relief and stunning detail. It is preserved in calcite with a layer of iron pyrite on the surface of the stems. Pyrite crinoids are hard to find and this is a very fine and unique example. Several cracks in the matrix from when it fell from the cliffs have been stabilised and it is a very solid fossil. It weighs 260 grams and has been coated in a reversible (soluble) lacquer for protection, which can be easily removed with white spirit if required.
Around 196 million years old, this fossil would make a wonderful addition to any collection.
Crinoids are echinoderms closely related to starfish and sea urchins, and have been around for many hundreds of millions of years. They still live today in the deep seas around the world.