This 1.6-pound carved agatized ammonite fossil from Madagascar measures 5.8 inches in diameter and 1.3 inches thick. It belongs to the genus Cleoniceras, which thrived during the Cretaceous Period. The polished surface highlights the genus’s distinctive, complex suture patterns—where the internal shell walls (septa) meet the outer shell—making it an exceptional specimen for geological study and fossil collection.
