Radiocarbon dating results from the Beakers and Bodies Project (original) (raw)

The radiocarbon dating programmes of The National Museums of Scotland

Antiquity, 2002

Since 1991, the Archaeology Department of the National Museums of Scotland (NMS) has been undertaking programmes of AMS radiocarbon dating of organic items in its collections, particularly wetland finds. This work was initially stimulated by the success of Caroline Earwood’s research on dating bog butter containers and other wooden vessels from the National collections (Earwood 1990; 1993a; 1993b; 1997), which demonstrated among other things that the practice of bog butter deposition in Scotland extended at least as far back as the early centuries AD.

Radiocarbon Results for the British Beakers

Radiocarbon, 1992

The beginning of the Bronze Age in the British Isles has traditionally been marked by the appearance, in the archaeological record, of Beaker assemblages, mainly characterized by the Beaker pottery form itself. Ceramic typologies based on this style, which is undoubtedly continental in origin, have been used both for relative dating and as evidence of the social and economic developments of the period. Systematic radiocarbon dating has been attempted for the continental European Beaker material (Lanting, Mook & van der Waals 1973), but no such program has been carried out on British material. An examination of the existing radiocarbon results for the British Beakers showed many to be flawed in some way, particularly in the use of materials, such as mature wood, where there is no a priori reason for assuming a direct relationship between sample death and context. An attempt has been made at the British Museum to test the validity of archaeologically derived chronologies for the Beake...

British Museum Natural Radiocarbon Measurements VIII

Radiocarbon: An International Journal of Cosmogenic Isotope Research, 1976

The following list consists entirely of dates for archaeologic samples from the British Isles measured since about mid-1970 up to June 1974*. The dates were obtained by liquid scintillation counting of benzene using a Model 3315 Packard Tricarb Liquid Scintillation Spectrometer. In general, procedures are as described in the previous date list (R, 1971, v 13, p 157; see also Burleigh, 1972). However, data processing was improved by means of a real-time link with a Hewlett Packard 2100A computer having 32K of core, which accepts readings from the counter at the end of each individual counting period. The computer monitors the accumulated sample counts and reports when the statistical error terms of these have reached previously chosen limits; final dates are then obtained on supplying the appropriate benzene sample weights and isotopic fractionation values. The system maintains a permanent record of all the data obtained from measurement of samples and reference standards and gives warning of any serious changes in counter performance. A full description of the capabilities of this system is given elsewhere (Hall and Hewson, in press). Finally, improvements were made to the bomb used for initial combustion of sample materials (Burleigh, 1974) and a new, stainless-steel, lithium reaction furnace (similar to that described by Polach and Stipp, 1967) was recently installed. Raw sample materials are systematically pretreated with dilute acid and alkali; but only collagen is used for antler and bone. The dates, relative to AD 1950, are based on the Libby half-life of 5570 years, are corrected for isotopic fractionation (relative to the PDB standard), and are expressed in radiocarbon years uncorrected for natural 14C variations. NBS oxalic acid is used as the modern reference standard. Descriptions, comments, and references to publications are based on information supplied by the persons who submitted the samples. ACKNOWLEDGMENTS We gratefully acknowledge the continued guidance and helpful criticism and advice of H Barker. SAMPLE DESCRIPTIONS ARCHAEOLOGIC SAMPLES A. British Isles 5730 ± 150 BM-91. High Rocks, Kent 3780 BC Charcoal from Layer 2 (Period III) of Site F at High Rocks, Tunbridge Wells, Kent, England (51° 07' N, 0° 14' E, Nail Grid Ref TQ * Dates obtained over the same period for samples from other geographic regions form the next list, British Museum IX.

British Museum Natural Radiocarbon Measurements X

Radiocarbon, 1979

The following list consists entirely of dates for archaeologic samples from the prehistoric flint mining site of Grime's Graves, Weeting, Thetford, Norfolk, England (52° 30' N, 0° 40' E, Natl Grid Ref TL 816898),

Holocene Variations In the Scottish Marine Radiocarbon Reservoir Effect

…, 2004

We assessed the evidence for variations in the marine radiocarbon reservoir effect (MRE) at coastal, archaeological Iron Age sites in north and west Scotland by comparing AMS measurements of paired marine and terrestrial materials (4 pairs per context). ∆R values were calculated from measurements on material from 3 sites using 6 sets of samples, all of which were deposited around 2000 BP. The weighted mean of the ∆R determinations was -79 ± 17 14 C yr, which indicates a consistent, reduced offset between atmospheric and surface ocean 14 C specific activity for these sites during this period, relative to the present day (∆R = ~0 14 C yr). We discuss the significance of this revised ∆R correction by using the example of wheelhouse chronologies at Hornish Point and their development in relation to brochs. In addition, we assess the importance of using the concepts of MRE correction and ∆R variations when constructing chronologies using 14 C measurements made on materials that contain marine-derived carbon.

British Museum Natural Radiocarbon Measurements VII

Radiocarbon, 1971

Dates listed below are based on measurements made from June 1968 to May 1970 by the liquid scintillation technique using benzene. In general, the experimental procedure is as described previously (Barker, Burleigh, and Meeks, 1969a) with a few changes in detail. Data are now processed by computer using a comprehensive Algol program written by Andrew Barker, King's College, Univ. of London. There is no need to standardize on any particular sample weight and, as the benzene synthesizer can also deal with samples in the range up to the equivalent of 9 gm of carbon in a single synthesis, the amount of sample available is now less critical. However, for older material, a minimum of 1 gm of carbon is required. Another factor contributing to efficiency of operation is the "bomb" technique for sample combustion (Barker, Burleigh, and Meeks, 1969b), also mentioned in the previous date list. Finally, during 1969, an MS20 double collection mass spectrometer was acquired and all dates (but not all those in this list) are now corrected for isotopic fractionation. Samples were pretreated for removal of contaminants, with dilute hydrochloric acid and, where appropriate, with dilute alkali also. Bone and antler samples were demineralized in low vacuum with 0.75 N hydrochloric acid at ambient temperature, leaving only the protein fractiori (collagen) which was washed and dried before combustion. Dates were calculated using the Libby half-life for C14 of 5568 years. Descripdons, comments, and references to publications are based on information supplied by the persons who contributed the samples. ACKNOWLEDGMENT Thanks are due to Miss G. I. Hassall, National Physical Laboratory, for isotopic fractionation measurements made in connection with the investigation of C14 age discrepancies using well-dated Egyptian materials.