Dear Dave, there are many references both from radiocarbon and stable
isotopic points of view. The methods strongly depend on how much
contamination there is and how fancy you want to go.The easiest is to use a
" Longin extraction" (see ref) and the fanciest (in case of severe
contamination) is extraction of collagen-specific tripeptides using enzymes
and HPLC (see refs onder my own humble name).  You can always drop in at our
lab!!
Best regards GJ

1.Ambrose, S.H. Journal of Archaeological Science 17, 431-451. (1990).
2.Bornstein, P. & Traub, W. The chemistry and biology of collagen 1- - (
Academic Press, New York., 1979).
3.Brown, T.A., Nelson, D.E., Vogel, J.S. & Southon, J.R. Radiocarbon 30,
171-177. (1988).
4.Van Klinken, G.J. & Hedges, R.E.M. Journal of Archaeological Science 22,
263-270 (1995).
5.Van Klinken, G.J., Bowles, A.D. & Hedges, R.E.M. Geochimica et
Cosmochimica Acta 58, 2543-2551 (1994).
6.Longin, R. Nature 230, 241-242. (1971).
7.Tuross, N., Fogel, M. & Hare, P.E. Geochimica et Cosmochimica Acta 52,
929-935. (1988).
8.Gurfinkel, D.M. Radiocarbon 29, 45-52. (1987).
9.DeNiro, M.J. & Weiner, S. Geochimica et Cosmochimica Acta 52, 2197-2206.
(1988).
10.Chisholm, B.S., Nelson, D.E. & Schwarcz, H.P. PACT 8, 391-397. (1983).





Gert Jaap van Klinken
Radiocarbon Accelerator Unit
Research Laboratory for Archaeology and the History of Art
University of Oxford
6 Keble Road, Oxford OX1 3QJ
Tel (+44) (01865) 273939   Fax (01865) 273932