Genuine Large Fossil Crinoid float bulb. Scyphocrinites (Mahoumacrinus)
Erfoud Region Morocco
Devonian age, Approximately 400 million years old.
Measuring approximately 130mm diameter x 110mm depth. Weight 2.4kg the orange colour is down to iron oxide in the fossil which may rub onto hands when handling. You will receive actual piece shown in pictures.
lobolith, or crinoid "float", is the bulbous root of a crinoid that served to some extent as a swimming apparatus, holding the crinoid stem and calyx in an upside down position in the water. The lobolith was chambered and likely filled with a gas produced by the crinoid to regulate its position within the water. This allowed the animal to float with the currents and move up and down in the water column. Considering most crinoids were held in place by a root-like system (holdfast), these loboliths are unique to a specific type of crinoid.
(Ref L4)