I would check the ART AND ARCHAEOLOGY TECHNICAL ABSTRACTS that your university library should have. I would also contact your nearest historical society museum and talk to their conservators. Anita Cohen-Williams; Reference Services; Hayden Library Arizona State University, Tempe, AZ 85287-1006 Tel: (602) 965-4579 FAX: (602) 965-9169 [log in to unmask] Owner: HISTARCH, SPANBORD, SUB-ARCH