> Regardless, however one wants to spin the RCD
> studies, of which over 400 samples were used of
> not just charcoal but short lived materials as
> well, one thing is for certain no matter how they
> are looked at, no matter how many were "tainted"
> or "thrown out" or whatever- there is no way to
> magically turn an average of +/- 200yrs older into
> thousands of years let alone tens of thousands. By
> the same token, as a whole this is not explained
> by "old wood" either. Egyptology is at fault for
> not accepting these dates and revising accordingly
> which at least they can take solace knowing they
> got even as close as they did.
I agree with your comment about old wood and disagree about the "spin". There's no need to invoke "magic".
A small contamination with new carbon can very significantly throw off very old dates by far more than a couple of centuries. That's because of the logarithmic nature of the decay in the C14/C12 ratio. And we have no reason to believe the contamination was very small at all. Every sample was taken from the surface which has been exposed to uncountable sources of modern carbon not the least of which is the very polluted air everything has been bathing in for many years 24/7. If the original was only a few centuries old then new carbon might throw off the dates by a few decades, but if a sample is, say, 10,000 years old, new carbon could make it seem many millennia newer. It's relatively simple ratio mathematics with (hopefully but, according to Onvlee not always) a calibration curve applied.
Nevertheless, the stated method (at least in the '95 study) was to collect surface samples that only contained at least a 1-2mm clump of "charcoal". How do we know if such mortar might only have been used during the 3rd millennium BC for restorations done by the adaption Dynastics and that the "original" mortar might have been more homogenous, might contain only smaller specks of carbon (if any at all) and so were summarily rejected. It's even possible that the original builders didn't use mortar on G1's core blocks at all and that all of the core mortar is "new".
Also, we really do not know with certainty when G1's casings were actually removed. The ancient historic reports are known to exaggerate, or report second hand information, so reports about a 1303 earthquake, etc. as the impetus to strip the stones are certainly possible, but not totally verified. Therefore it's possible that those core blocks have been exposed to "modern" carbon for far longer than traditionalist thinking. Even so, a 700 year bath in open-air, environmental carbon is a huge contamination. It's not like someone accidentally touched something known to have been deep inside an unbreached cave for millennia.
Considering the ongoing dispute about the age of that erosion observed in stonework on Giza, the real and significant problem of "modern" contamination in surface samples, the bias in selecting only large clumps of charcoal, the uncertainty of whether the samples might have been a newer subset of mortar from more recent restorations, and the clear logical flaws in the investigations, at least regarding the '95 report, we really don't have a strong basis for assessing the actual error in accuracy of the data.
[edit: see here as a post hoc supplement to the above]
How can any of us ever know, when all we can do is think?
Edited 1 time(s). Last edit at 18-Jun-16 17:11 by Origyptian.