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INVESTIGATION OF A SURFACE TARNISH FOUND ON 19TH-CENTURY DAGUERREOTYPESLEE ANN DAFFNER, DAN KUSHEL,  & JOHN M. MESSINGER
 
 
 5 SOLVENT TESTSA series of basic solvent tests were conducted on one of the plates exhibiting fluorescence. The spot tests were conducted in a fume hood under UVC illumination. The fluorescence was immediately eliminated by xylene and N,N-dimethyl formamide, and remained so after complete evaporation of the solvent. The fluorescence was not affected by water, ethanol, 1 M HCL, or ethylene diamine tetraacetic acid (EDTA) trisodium salt. |