Even if not, paper from different locals are going to have different sources. Think bamboo fibers, but isotope just means extra neutrons, which as a small percentage represent is as true for carbon and oxygen as it is for uranium.
Could just mean they did version of carrbon dating. But they weren't after the date, just classifying into lot groups, and noting where the anomolies fall (likely in a single lot, printed elsewhere)
Even if not, paper from different locals are going to have different sources. Think bamboo fibers, but isotope just means extra neutrons, which as a small percentage represent is as true for carbon and oxygen as it is for uranium.
Could just mean they did version of carrbon dating. But they weren't after the date, just classifying into lot groups, and noting where the anomolies fall (likely in a single lot, printed elsewhere)