In the early to mid-1970s, the U.S. Federal government, and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), each passed laws regulating the import & export of endangered animals & their parts, like whale teeth. See C.I.T.E.S. and E.S.A. Regulations.
These regulations prompted several companies to manufacture resin replicas of both raw whale teeth and scrimshawed whale teeth. Some are obvious copies (Image #1), while others are realistic reproductions cleverly engineered to fool the average antique dealer or novice collector (Image #2), and require marking as such (Image #3). Read this WorthPoint Research Library article: How to Discern Authentic Whale Tooth Scrimshaw from Resin “Fakeshaw”.
Forgers quickly found legal ivory, such as hippopotamus teeth (Image #4), boars tusks, and elephant tusk tips, which could be re-shaped to resemble authentic whale teeth. Large animal bone was also re-shaped to resemble authentic whale teeth. Read this WorthPoint Research Library article: Discerning Authentic Scrimshawed Whale Teeth From Re-Shaped Bone & Hippo Teeth.
And finally, sophisticated forgers intentionally scrimshawed old-looking scrimwork onto real whale teeth, to which fake patina is added to appear antique (Image #5). Read this WorthPoint Research Library article: Distinguishing Authentic Antique Scrimshaw from Fraudulent Ivory
Words used to describe any scrimshaw that is not authentic are: faux, reproduction, repro, fakeshaw, polymer, “cultured ivory”, “antiqued”, facsimile, ivoryite, resin, plastic, etc.
This WorthPoint collection has examples as mentioned above: Not Quite Authentic Scrimshaw
Before a novice collector purchases a scrimshawed whale tooth, showing photos to an experienced scrimshaw collector is advised. Remember that general antique dealers rarely see authentic antique scrimshaw, and may be easily fooled by a good fake.