The calibration curve for the early Holocene — the time period when the Hourglass Cave man lived — is reasonably well-established.

The dendrochronological record (tree-ring data) that underpins the radiocarbon calibration curve extends back approximately 13,000 years, providing a precise independent chronology against which radiocarbon measurements can be calibrated for most of the Holocene.

The uncertainty in the calibration at 8,800 calendar years is substantially smaller than for much older samples where the calibration curve depends on less precise records.

The contamination concern — the possibility that younger organic material has been incorporated into the bone sample and caused the radiocarbon date to appear more recent than it really is — is managed by selecting specific fractions of bone for dating.