Large Orthoceras Deathplate Slab - Morocco

This Orthoceras "Deathplate" slab is a cut and polished piece of dark limestone with the fossilized remains of Orthoceras, ancient marine cephalopods, preserved within this matrix.  

This beautiful specimen is sold as seen, and thus you will receive this exact piece, containing approximately 6 polished Orthoceras ("Orthocones"). The white parts of each are pure calcite crystals that filled the hollow shells of these cephalopods millions of years ago whilst the black/grey parts are organic-rich ocean mud. 

A stunning display specimen from the Erfoud Region, Morocco. Slab measures approx. 27cms x 14cms x 5cms and weighs approx. 1952g.

Orthoceras (meaning "straight horn", were ancient marine cephalopods that inhabited prehistoric seas over 400 million years ago, during the Ordovician/Devonian period. These squid-like animals possessed long conical shells and regulated buoyancy using internal chambers and a central tube called a siphuncle. They were the prehistoric ancestors of today's marine cephalopod molluscs, including the cuttlefish, nautilus, octopus and squid.

Millions of years ago, massive groups of these squid-like creatures were deposited on the ancient seafloor, possibly as a result of either the result of post-mating mass die-offs or currents and storms sweeping dead shells and individuals together into one spot. Then the hollow chambers of the shells filled with sediment and minerals and over time pressure turned the surrounding lime-rich mud into limestone or black marble. The "deathplate effect" of an Orthoceras slab is thus the visual presentation of this mass mortality assemblage (thanatocoenosis) cut and polished into a display piece.