They have tightly coiled shells, whose overall shape is basically that of an elongated cone.
Pieces incorporated in jewelry have been marketed as ammolite, calcentine and korite. Some fossiliferous rocks have been selected for use as gemrocks because of the identities of their contained fossils; others have been chosen because of the patterns their included fossils give when cut in certain directions.
They have tighly coiled shells, whose overall shape is basically that of an elongated cone.
The name Turritella comes from the Latin word turritus meaning "turreted" or "towered" and the dimunitive suffix -ella.
"Turritella Agate" is based on a case of mistaken identity.
This intriguing stone consists of fossils of freshwater snails that were deposited in a series of ancient lakes in present-day Wyoming.