No indication on how the date was established. Was it exactly 6,200 years ago, to the hour?
“Was it exactly 6,200 years ago, to the hour?”
The universe did not even exist 6,000 years ago. Okay, 6,016 years, 258 days, 23 hours, and 39 minutes. If you live in the Eastern timezone.
Carbon dating most likely. I think is accurate to +/- 50 years........
From the linked paper http://advances.sciencemag.org/content/2/9/e1501623.full
The earliest textiles decorated with blue at Huaca Prieta were excavated from stratum 44 in J. Birds HP-3 trench. Although not decorated with indigo, the earliest cotton yarn is from stratum 52, which is radiocarbon-dated at 68826657 cal BP [sample AA82121; see the study by Dillehay et al. (3)]. The next radiocarbon-dated level is stratum 35 at 58485585 cal BP (sample AA86948 on charcoal from an intact hearth), suggesting that the two textiles from stratum 44 are about 6200 to 6000 years old.
(BP = before present)
Ask Ruth Ginsburg. I hear she was around back then.