A SPECTROSCOPIC INVESTIGATION OF PIGMENT AND CERAMIC SAMPLES FROM COPÁN,HONDURAS*

A combination of micro‐Raman spectroscopy, micro‐infrared spectroscopy and SEM–EDX was employed to characterize decorative pigments on Classic Maya ceramics from Copán, Honduras. Variation in red paint mixtures was correlated with changing ceramic types and improvements in process and firing techniques. We have confirmed the use of specular hematite on Coner ceramics by the difference in intensities of Raman bands. Different compositions of brown paint were correlated with imported and local wares. The carbon‐iron composition of the ceramic type, Surlo Brown, was confirmed. By combining micro‐Raman analysis with micro‐ATR infrared and SEM–EDX, we have achieved a more comprehensive characterization of the paint mixtures. These spectroscopic techniques can be used non‐destructively on raw samples as a rapid confirmation of ceramic type.     

RADIOCARBON MEASUREMENT BY ACCELERATOR MASS SPECTROMETRY: AN EARLY SELECTION OF DATES

Dates from the first runs of the Oxford Radiocarbon Accelerator Unit span the range from present to c. 17,000 bp, with errors (1 s.d.) from ± 100 to ± 300 years. Material dated comprises bone, wood, charcoal, seeds, organic residues in pottery, and charcoal inclusions in slag.     

X-RAY FLUORESCENCE ANALYSIS OF MUSEUM OBJECTS: A NEW INSTRUMENT

A new X-ray fluorescent analyser is described which uses a miniature X-ray tube or radioisotope source as alternative means of primary excitation. The advantages of this approach as compared to previous methods, particularly where elements low in the periodic table are concerned, is discussed. The second part of the paper describes an application of the technique. The non-destructive analysis of valuable ceramics, where elements low in the periodic table are important for differentiation purposes, has previously presented a problem. By using the ‘Isoprobe’such measurements are possible. In this instance the separation of early Chinese porcelains into Northern and Southern production groups is shown to be possible. Although samples have been ground from the wares for comparison with optical emission spectrometry, it is shown that analysis of the unglazed portions of the pots themselves gave similar results.     

DEVELOPMENT‐DRIVEN ARCHAEOLOGY: BANE OR BOON FOR BIOARCHAEOLOGY?

Summary.   Through much of the world there is a move towards policies of in situ preservation of the buried archaeological heritage, typically supported by small-scale investigative excavations (often called 'evaluations'). In this review we attempt to judge the success of these policies in England and Wales, from the standpoint of bioarchaeology. We consider particularly the value of data for plant and insect macrofossils from trial excavations associated with development (a) in producing information which contributes towards research agendas, and (b) as a guide to the preservational condition of organic archaeological deposits.