UCLA Radiocarbon Dates XI

Abstract

The radiocarbon dates reported in this list are almost all based on collagen measurements from human archaeologic bone material. This collagen was isolated according to the methods developed by Berger, Horney and Libby (1964), Ho, Marcus and Berger (1969), Longin (1971) and Protsch (1973). All samples were counted as CO 2 gas at close to 1 atm in a 7.5L proportional counter with three energy channels. The 14 C dates reported are calculated with the Libby half-life of 5568 ± 30 years as required by convention. 13 C measurements were used to normalize to −25‰ in the standard manner. The biospheric standard is 95% the count rate of NBS oxalic acid for radiocarbon laboratories. Background is based on CO 2 obtained from marble. The accuracy of counter operation is checked against historically dated wood from the funerary boat of Sesostris III, 1872 −8 +4 bc (Hayes, 1962). The 14 C ages are not tree-ring calibrated.