Among this collection, three Predynastic human mummies gave coherent radiocarbon results, showing that they were buried during the Nagadean period.2 In contrast, the observation of two other mummies (16) revealed classical embalming traces (nose padding, right side incision) showing that they had undergone a funeral ritual of mummification.He said that his team and the laboratories they employed took special care to avoid contamination.
The theoretical limit for C-14 dating is 100,000 years using AMS, but for practical purposes it is 45,000 to 55,000 years.
If dinosaur bones are 65 million years old, there should not be one atom of C-14 left in them.
If the radiocarbon were intrinsic to the sample, there would be no change in the radiocarbon ratio with sample current. However, if the radiocarbon were coming from ion source memory or elsewhere in the accelerator, it should give a count rate independent of ion source current.
Normalizing the radiocarbon count rate to the ion source current, which is predominantly C, would result in higher radiocarbon content for lower source currents, as observed.
This data provides clear evidence that at least a significant fraction of the radiocarbon detected by Taylor and Southon in diamond measurements did not come from the diamonds themselves and thus could not be “intrinsic radiocarbon.” In his 2008 critique Bertsche references the Taylor and Southon (2007) paper describing their application of accelerator mass spectrometry (AMS) to natural diamonds.
Bertsche calls attention to the authors’ statement, “The oldest C level with high ion current was restricted to only a subset of the authors’ data.
Radiocarbon dating of bone collagen routinely focuses on the extraction of bulk proteins that are then purified before radiocarbon measurement.
However, the extracted bulk gelatin can be heterogeneous and include, or be cross-linked to, potential contaminants from the depositional environment, such as humic and fulvic acids, rootlets, cellulose, sediments, and other plant and animal remains including amino acids from bacteria and microorganisms (1, 2).
For some samples curated in museums, additional contaminating compounds, such as glues, consolidants, and fumigants, can affect accurate dating, if not removed.