Table 2.

Radiocarbon determinations from the Grotte du Renne, Arcy-sur-Cure

OxA no.14C age B.P.Used, mgYield, mg%Yield%Cδ13C, ‰C/N atomic ratio
Level V
 OxA-21567*23,070 ± 210456.−20.13.3
 OxA-21568*23,180 ± 210572.74.50.842.5−18.73.4
Level VI
 OxA-X-2279-1234,850 ± 6001,0106.10.644.6−21.03.3
Level VII
 OxA-2168235,000 ± 6501,1307.20.644.1−21.13.3
 OxA-21569*36,500 ± 1,300479.54.30.941.3−19.73.2
 OxA-21570*34,600 ± 800236.53.41.442.4−19.13.2
 OxA-21571*34,050 ± 750491.66.61.341.1−18.73.2
 OxA-21572*34,600 ± 750528.910.82.042.7−18.63.3
Level VIII
 OxA-X-2279-1435,450 ± 7501,3104.10.342.2−20.23.3
 OxA-2168340,000 ± 1,2009907.30.744.5−21.03.3
 OxA-21573*36,800 ± 1,000507.16.91.441.6−19.23.2
Level IX
 OxA-21574*38,800 ± 1,300551.213.22.442.1−19.03.2
 OxA-21575*32,100 ± 550664.311.61.742.5−19.03.2
Level X
 OxA-21565*37,900 ± 90060012.32.140.0−20.73.2
 OxA-21557*38,100 ± 1,3002402.71.141.1−20.63.3
 OxA-21576*40,800 ± 1,700529.−18.43.2
 OxA-X-2222-21*23,120 ± 1905063.80.843.4−20.23.6
 OxA-21577*34,650 ± 800636.25.40.841.8−19.43.2
 OxA-X-2226-7*38,500 ± 1,300620.13.20.544.3−19.53.7
 OxA-21590*21,150 ± 160470.−20.73.2
 OxA-21591*34,750 ± 750620.29.91.644.4−18.93.3
 OxA-21592*36,200 ± 1,100213.−19.43.4
 OxA-21593*35,300 ± 900440.37.91.842.1−18.83.3
 OxA-X-2226-12*41,500 ± 1,900458.33.00.743.1−18.33.3
 OxA-X-2226-13*39,000 ± 1,400451.23.40.844.2−18.63.3
 OxA-X-2279-1840,600 ± 1,3001,1005.30.543.7−21.23.2
 OxA-X-2279-44*48,700 ± 3,6009705.10.537.3−20.93.3
 OxA-X-2279-45*40,900 ± 1,3001,0206.80.737.4−20.43.3
 OxA-X-2279-46*38,700 ± 1,0001,0006.50.741.6−20.43.3
Level XII
 OxA-21594*37,000 ± 1,000399.66.91.744.6−19.03.3
 OxA-21595*38,200 ± 1,200418.75.91.442.5−20.73.3
  • All are ultrafiltered gelatin determinations. Stable isotope ratios are expressed in ‰ relative to Vienna Pee-Dee Belemnite (vPDB). Mass spectrometric precision is ±0.2‰. The weight used is the amount of bone pretreated, and the yield represents the weight of gelatin or ultrafiltered gelatin in milligrams. %Yield is the wt% collagen, which, ideally, should not be <1wt% at the Oxford Radiocarbon Accelerator Unit (ORAU). This is the amount of collagen extracted as a percentage of the starting weight. Collagen is not well preserved at the site. %C is the carbon present in the combusted gelatin. For ultrafiltered gelatin, this averages 41.0 ± 2%. C/N is the atomic ratio of carbon to nitrogen. At the ORAU, this is considered acceptable if it ranges between 2.9 and 3.5. In one case, a sample (OxA-X-2226-7) yielded a C/N of 3.7, which indicates the addition of carbon; therefore, one should view this result with caution. Initially, we calculated this as a ratio greater than age, and we accepted the result in our modeling. It was not flagged as an outlier. Subsequent recalculations using more recently obtained background measurements resulted in a finite age. We include it but acknowledge the potential for a contamination signal. OxA-X- prefixes are given where the chemistry is non-routine or experimental, or where the yields of %wt collagen or extracted collagen are lower than, or approaching, the thresholds set at the ORAU. Details of the sample materials dated are provided in Table S3 (SI Methods).

  • *Bones were pretreated before collagen extraction with a solvent sequence as a precaution before accelerator mass spectrometry dating. This is designed to remove any consolidants or glue-based contaminants. Careful observation and sampling mitigated against the presence of this, with the exceptions described in the paper.