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<p>[QUOTE="necollectors, post: 1423773, member: 12723"]SYNTHETIC IVORY</p><p><br /></p><p>Manufactured ivory substitutes fall into three categories:</p><p><br /></p><ul> <li>composites of an organic resin and an inorganic material</li> <li>composites of casein and a resin material</li> <li>composites of ivory sawdust with a binder or resin</li> </ul><p>Pure casein shows a UV fluorescence similar to ivory. The chemical structures, however, are easily distinguishable by FT - IR.</p><p><br /></p><p>Ivory sawdust compositions are not ivory substitutes in the true sense of the term. They are subject to the same international trade controls and permit requirements as solid ivory products.</p><p><br /></p><p>The images are examples of manufactured ivory substitutes. The left one is an early twentieth century celluloid, and the right one is a modern polyester resin. Note the attempt to mimic the proboscidean pattern.</p><p><br /></p><p><a href="https://www.fws.gov/lab/images/syntheti.jpg" target="_blank" class="externalLink ProxyLink" data-proxy-href="https://www.fws.gov/lab/images/syntheti.jpg" rel="nofollow"><img src="https://www.fws.gov/lab/images/ivory_synthetic_clip_image001.jpg" class="bbCodeImage wysiwygImage" alt="" unselectable="on" /></a> <a href="https://www.fws.gov/lab/images/syntheti.jpg" target="_blank" class="externalLink ProxyLink" data-proxy-href="https://www.fws.gov/lab/images/syntheti.jpg" rel="nofollow">Click to see examples of manufactured ivory substitutes!</a></p><p><br /></p><p>Regardless of the appearance or chemical composition of the manufactured ivory substitutes, they all share a common identifying characteristic. When ultraviolet light is shined on a manufactured ivory products they absorb the ultraviolet light exhibiting a dull blue appearance. Ivory, on the other hand, has a white/blue florescent appearance.</p><p><br /></p><p>Identification of manufactured ivory substitutes is facilitated if standards of the manufactured ivories are available for comparative purposes when using the ultraviolet light.</p><p><br /></p><p><a href="https://search.usa.gov/search?query=ivory&submit=Search&v%3Aproject=firstgov&affiliate=Forensics_Laboratory" target="_blank" class="externalLink ProxyLink" data-proxy-href="https://search.usa.gov/search?query=ivory&submit=Search&v%3Aproject=firstgov&affiliate=Forensics_Laboratory" rel="nofollow">https://search.usa.gov/search?query=ivory&submit=Search&v:project=firstgov&affiliate=Forensics_Laboratory</a>[/QUOTE]</p><p><br /></p>
[QUOTE="necollectors, post: 1423773, member: 12723"]SYNTHETIC IVORY Manufactured ivory substitutes fall into three categories: [LIST] [*]composites of an organic resin and an inorganic material [*]composites of casein and a resin material [*]composites of ivory sawdust with a binder or resin [/LIST] Pure casein shows a UV fluorescence similar to ivory. The chemical structures, however, are easily distinguishable by FT - IR. Ivory sawdust compositions are not ivory substitutes in the true sense of the term. They are subject to the same international trade controls and permit requirements as solid ivory products. The images are examples of manufactured ivory substitutes. The left one is an early twentieth century celluloid, and the right one is a modern polyester resin. Note the attempt to mimic the proboscidean pattern. [URL='https://www.fws.gov/lab/images/syntheti.jpg'][IMG]https://www.fws.gov/lab/images/ivory_synthetic_clip_image001.jpg[/IMG][/URL] [URL='https://www.fws.gov/lab/images/syntheti.jpg']Click to see examples of manufactured ivory substitutes![/URL] Regardless of the appearance or chemical composition of the manufactured ivory substitutes, they all share a common identifying characteristic. When ultraviolet light is shined on a manufactured ivory products they absorb the ultraviolet light exhibiting a dull blue appearance. Ivory, on the other hand, has a white/blue florescent appearance. Identification of manufactured ivory substitutes is facilitated if standards of the manufactured ivories are available for comparative purposes when using the ultraviolet light. [URL]https://search.usa.gov/search?query=ivory&submit=Search&v%3Aproject=firstgov&affiliate=Forensics_Laboratory[/URL][/QUOTE]
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