20313 - Cut & Polished 2.53 Inch Cleoniceras sp Lower Cretaceous Ammonite Madagascar - Agatized

†Cleoniceras sp, Parona and Bonarelli 1897 (ammonite)

Cephalopoda - Ammonitida - Cleoniceratidae

Cleoniceras is a rather involute, high-whorled hoplitid from the Lower to basal Middle Albian of Europe, Madagascar, and Transcaspian region. The shell has a generally small umbilicus, arched to acute venter, and typically at some growth stage, falcoid ribs that spring in pairs from umbilical tubercles, usually disappearing on the outer whorls.

These ammonites present an impressive mineralization, both in its outer shell and in its chambers and internal structure. The mineralization is produced in agate, with beautiful iridescent tones typical of this variety of quartz.