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Sniffer unveiled

If a coin has been waxed, caulked or otherwise altered, the “Coin Sniffer” will know.

This article was originally printed in the latest issue of Numismatic News.
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If a coin has been waxed, caulked or otherwise altered, the “Coin Sniffer” will know.


The Professional Coin Grading Service, Santa Ana, Calif., a division of Collectors Universe, displayed its PCGS Coin Sniffer at a luncheon on Jan. 7 at the Tampa Convention Center during the 56th Annual Florida United Numismatists Coin Show.

The PCGS Coin Sniffer, an invention of Richard Haddock, can currently detect around 40 different foreign substances on the surface of a coin – substances that are often used by coin doctors to alter a coin’s appearance and attempt to raise its value.

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The Sniffer not only identifies the areas on the coin where any organic substance, such as nose grease, putty, caulk, and Turtle Wax, can be found but also, in many cases, the type of substance. A portion of the equipment used in the process was on display at the luncheon.

According to the firm’s website, the Sniffer utilizes “energy dispersive X-ray spectrometry (EDX), Fournier Transform Infra-Red Spectral analysis (FT-IR), Raman Spectroscopy and other similar analytical techniques” to analyze the surfaces of a coin in matter of seconds.

PCGS President Don Willis also detailed the workings of its Secure Plus technology and the PCGS Ray Gun.

The Secure Plus technology, introduced last year and now in its second generation of hardware, provides a method for the grading service to document each coin’s characteristics by producing a “fingerprint” of the coin by using multiple lasers during the scanning process. It also takes pictures of both sides of the coin.

The technology is designed to detect resubmissions in which the coin has been altered in an effort to enhance its appearance and receive a higher grade. A commemorative coin that upon its first submission for grading was white and came back the second time toned was used as an example.

Once a suspected alteration is detected, the information is forwarded to the verifier for final determination as to whether to grade or to reject and “body bag” the coin. The “fingerprint” records can also be used to identify a lost or stolen coin should it be resubmitted to PCGS.

Willis also showed a screen image of the PCGS Ray Gun. A futuristic-looking piece of equipment, the ray gun, which is in active use by PCGS at a cost of around $50,000 per unit, shoots a high energy beam at a coin that allows the device to detect any inorganic material on the surface of the coin that might indicate an alteration. The gun has its own built-in periodic table to identify the various metals.
Metal solutions such as solder and indium are sometimes used by coin doctors in the process of repairing or enhancing a coin’s appearance.

Willis said this would be the last public appearance of the PCGS Coin Sniffer in order to protect the technology and to prevent coin doctors from learning of advances.

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