Cameron A long time ago..... calcified tissue chemists showed that hydrazine gives by far the best results for deproteinating bone. I tried their method, which works well, but in the end decided that hydrazine was a little too dangerous for the benefits received - at that time I did not need to eliminate organics entirely. The reference: Termine, JD et al (1973) Hydrazine-deproteinated bone mineral. Calc. Tiss. Res. 12, 73-90. (This journal is now called Calc. Tiss. International I think). In my opinion any serious heating procedure is bad news for isotopes in any components of bone. Good luck Julia Lee-Thorp Dr Julia Lee-Thorp Department of Archaeology, Faculty of Science University of Cape Town, Private Bag, Rondebosch 7701 South Africa Tel. 027-21 6502350 Fax. 027-21 6502352