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2024-08-27 21:48:20 -05:00
Center for Applied Isotope Studies
RADIOCARBON ANALYSIS REPORT
April 10, 2007
Hugo Miller 1215 Bryson Rd. Columbus, OH 43224-2009
Dear Mr. Miller
Enclosed please find the results of 14C Radiocarbon analyses and Stable Isotope Ratio δ13C and δ15N analyses for the samples received by our laboratory on February 23, 2007.
UGAMS# Sample Material Size, mg δ13C Radiocarbon pmC I.D. (‰) 13C Corrected Age (YBP±1s)
01935 P-H-3a bioapatite 1.00 -6.4 25670±220 4.09±0.12 01936 P-H-3a charred bone 0.47 -15.7 25170±230 4.36±0.12 01937 P-H-3a collagen 0.59 -22.7 23170±170 5.59±0.12 01938 P-H-3a humic acid 0.35 -21.5 2560±70 72.68±0.59
The bone was cleaned and washed, using ultrasonic bath. After cleaning, the dried bone was gently crushed to small fragments. The charred bone was treated with 5% HCl at the temperature 80°C for 1 hour, then it was washed and with deionized water on the fiberglass filter and rinsed with diluted NaOH to remove possible contamination by humic acids. After that the sample was treated with diluted HCL again, washed with deionized water and dried at 60°C.The prepared samples was transferred to quartz tube and combusted at 900oC. The humic acid solution was treated with 6N HCl to precipitate humic acid. The precipitate was centrifuged to separate them. The precipitate was washed with deionized water, dried in quartz tube for combustion, copper oxide was added for oxidation and the sample was combusted at 900oC. The crushed bone was treated with diluted 1N acetic acid to remove surface absorbed and secondary carbonates. Periodic evacuation insured that evolved carbon dioxide was removed from the interior of the sample fragments, and that fresh acid was allowed to reach even the interior micro-surfaces. The chemically cleaned sample was then reacted
under vacuum with 1N HCl to dissolve the bone mineral and release carbon dioxide from bioapatite. The crushed bone was treated with 1N HCl at 4oC for 24 hours. The residue was filtered, rinsed with deionized water and under slightly acid condition (pH=3) heated at 80oC for 6 hours to dissolve collagen and leave humic substances in the precipitate. The collagen solution is then filtered to isolate pure collages and dried out. The dried collagen was combusted at 575oC in evacuated/sealed Pyrex ampoule in the present CuO. The resulting carbon dioxide was cryogenically purified from the other reaction products and catalytically converted to graphite using the method of Vogel et al. (1984) Nuclear Instruments and Methods in Physics Research B5, 289-293. Graphite 14C/13C ratios were measured using the CAIS 0.5 MeV accelerator mass spectrometer. The sample ratios were compared to the ratio measured from the Oxalic Acid I (NBS SRM 4990). The sample 13C/12C ratios were measured separately using a stable isotope ratio mass spectrometer and expressed as δ13C with respect to PDB, with an error of less than 0.1‰.
The quoted uncalibrated dates have been given in radiocarbon years before 1950 (years BP), using the 14 C half-life of 5568 years. The error is quoted as one standard deviation and reflects both statistical and experimental errors. The date has been corrected for isotope fractionation. Use of the corrected date assumes the material originally had a δ13C composition of -25‰.
If the dates are to be published, please quote the UGAMS numbers, as it identifies our laboratory as having produced the dates.
If we can be of further assistance, or you wish to discuss these results, please do not hesitate to contact me.
Sincerely,
Dr.Alexander Cherkinsky
Center for Applied Isotope
Studies
University of Georgia
Tel: (706) 542-1395 E-mail: FAX: (706) 542-6106 acherkin@uga.edu
INVOICE
April 10, 2007
Results To: Invoice To:
Hugo Miller 1215 Bryson Rd. Columbus, OH 43224-2009
Invoice Nos.: 7802
Description of Work: 4 Radiocarbon AMS (14C) analysis of charcoal @ $450.00 1 Collagen extraction @$50.00 1 bioapatite preparation @$50.00 1 humic acid extraction @$75.00 4 Stable Isotope Ratio (δ13C) analyses (included)
Total Samples: 4 UGAMS 01935 through 01938.
Please Pay This Total Amount ........................US$1975.00
Make Check Payable To ...............................University of Georgia/CAIS
Remit Payment to .................................... Center for Applied Isotope Studies C.A.I.S. Building 120 Riverbend Rd. Athens, GA 30602-4702
Invoice Submitted by....................................Alexander Cherkinsky
Center for Applied Isotope Studies
120 Riverbend Road • Athens, Georgia 30602-4720 Telephone 706.542.1395 • Fax 706.542.6106 * cais@uga.edu An Equal Opportunity/Affirmative Action Institution