(Internal #S-800-124).  This is a genuine ELEPHAS or PACHYDERM FISH shark egg case or casing, also known as an Australian Ghost Shark (Callorhinchus Milii).

From Australia

Average size: 5-5/8” to 6-1/2 long x 2-3/4" wide

 ELEPHAS FISH EGG CASINGS

(Australian Ghost Shark) (Callorhinchus Milii)

A cartilaginous fish (Chondrichthyes) belonging to the subclass Holocephali (chimaera). Sharks, rays and skates are the other members. Alternative names include elephas makorepe, whitefish, plough-nose chimaera, or elephas fish. It is found off South Australia, including Tasmania, and south of East Cape and Kaipara Harbour in New Zealand.  From spring to autumn, adults migrate inshore to estuaries and bays and females lay their eggs on sandy or muddy substrates. The eggs are contained in large yellowish capsules. The egg partially opens enabling seawater to flow in to the egg capsules after a few months and juveniles emerge from the capsule after six to eight months as about 12 cm (4.7 in) in length.

An egg case or egg capsules are made of collagen protein strands. Because they are lightweight, they are commonly washed up by the sea, often found at the strandline, the farthest point of the high tide. The egg cases that wash up on beaches are usually empty, the young fish having already hatched out.  

This is the exact item you would receive.

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