AMS also tends to be more precise than conventional radiocarbon dating for very old samples, where the number of decay events per unit time becomes very small.

For samples near the limit of radiocarbon dating — roughly 50,000 years for AMS, beyond which so little carbon-14 remains that measurement becomes unreliable — the calibrated calendar age can diverge significantly from the raw radiocarbon age.

The calibration curve for the period relevant to Bluefish Caves — roughly 20,000 to 30,000 years ago — incorporates data from multiple sources and has been refined progressively as more calibration records have become available.

The dates produced for the Bluefish Caves cut-marked specimens in the 2017 study are expressed in calibrated calendar years BP, reflecting the conversion from raw radiocarbon measurements to actual calendar ages using the best available calibration data.