Spectrochimica Acta Part A 57 (2001) 1325 – 1338 A study of amber and copal samples using FT-Raman spectroscopy Rachel H. Brody a,b,1 , Howell G.M. Edwards a, *, A. Mark Pollard b,1 a Department of Chemical and Forensic Sciences, Uniersity of Bradford, Bradford, West Yorkshire BD71DP, UK b Department of Archaeological Sciences, Uniersity of Bradford, Bradford, West Yorkshire BD71DP, UK Received 20 November 2000; accepted 23 December 2000 Abstract FT-Raman spectra were collected from fossil resins originating from a variety of geographical locations. The spectral profiles of most of the fossil resins could be related to modern resins containing diterpenoid components with predominantly labdane skeletons. The spectra collected from the fossil resin sample from Borneo differed from other fossil resins and was found to contain triterpenoid components. The differences in the spectral profile of fossil resins containing diterpenoid components are shown to relate to differences in level of maturation rather than geographical origin. FT-Raman spectra of fossil resins cannot be used to distinguish source although the degree of maturation can be used as an indicator to narrow the range of possible geographical origins. © 2001 Elsevier Science B.V. All rights reserved. Keywords: Amber; Copal; Fossil resins; FT-Raman spectroscopy; Maturation www.elsevier.nl/locate/saa 1. Introduction Amber and copal are terms used to describe fossilised resins, the former term conventionally referring to geologically more mature samples. Maturation is a term used to describe the pro- cesses during burial that transform a resin into copal or amber. The changes are largely due to oxidative processes arising from the conditions in the geological environment i.e. temperature, pres- sure and water levels. The extent of maturation of a sample is dependent on both thermal history and length of burial. Deposits of fossilised resins occur around the world with the best-known source of amber being in the Baltic region of Northern Europe. It is of interest to several differ- ent disciplines (including archaeological research) if the geographical origin of amber or copal sam- ples can be determined and in this respect, several different analytical techniques have been em- ployed. Hitherto, infrared spectroscopy has been the method of choice after Beck and co-workers [1,2] discovered that amber from the Baltic region could be differentiated from other European am- * Corresponding author. Tel.: +44-1274-233787; fax: +44- 1274-235350. E-mail addresses: h.g.m.edwards@bradford.ac.uk (H.G.M. Edwards), a.m.pollard@bradford.ac.uk (A.M. Pollard). 1 Fax: +44-1274-235190. 1386-1425/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved. PII:S1386-1425(01)00387-0