Does anyone know of a carbon-containing material with a del13C of plus25 to
30permil? We have isolated a white evaporation deposit from a rock surface
(within a study of rock painting) with this odd value..

Thanks very much, GJ
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Dr. Gert Jaap ("GJ") 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