Document analyst, U.S. Postal Service, Crime Laboratory, San Bruno, CA
Document analysist, U.S. Treasury Department, Bureau of Alcohol, Tobacco and Firearms, Treasure Island, CA
(Received 12 August 1987; accepted 8 September 1987)
It is well recognized that the powdered mixture of methylene blue and starch is highly sensitive for the purpose of detecting physical erasure sites which are virtually undetectable by other methods. Also well known are the problems associated with this method, for example, permanent discoloration of the document upon assimilation of moisture. This paper details the successful search for a formula possessing the sensitivity of the methylene blue/starch mixture minus its disadvantages.
Paper ID: JFS12488J