The date seems to now go back to the 6th century BCE.
the article below has information from the New York Times. The Journal article link is also given.
New Clues May Change Buddha’s Date of Birth
article published online in the December issue of the international journal Antiquity.
According to Dr. Keir Strickland (co-Author of the article);
On dating the sand:
"Archaeology Department Orkney College (Keir here): Hi John E. Mead - we used OSL (optically stimulated luminescence) - well, I say "we" - the OSL sampling was done by Prof. Ian Simpson (University of Stirling) and processed at SUERC. OSL dates the last exposure of certain crystalline materials (usually quartz) to light - for a reasonably accurate summary of the technique see;http://en.wikipedia.org/wiki/Optically_stimulated_luminescence"
OSL is new to me... I wonder if they've thought about using that technique to date the Pyramids? Either using OSL or Thermoluminescence. They should give it a shot!
I had no idea either. I had to ask <g>
there is sand in at least one hidden room in the great pyramid. I;ll have to check around and see if that was done,, feasible etc.
getting permission to get anything from it is near impossible. The did get some straw from some mortar on the inside. .... that took forever to get the permit. It was considered inconclusive since the stuff could have been a patch (? other ?) at a later date.
I saw some information quickly where they stated that this OSL is probably the most reliable in testing limestone... interesting enough, we just had a conversation about limestone being used in the pyramids.. There has got to be some info on it or why they haven't. I did some searching, I found this Liritzis document, but it's pretty technical... Although it states that they tested limestone from The Valley Temple Giza, they did not include a date for that for whatever odd reason.
If Buddha's date of birth is finally altered a lot of history texts have to be re-written, as the academics had considered it a settled matter and had modified the dates of number of other events to suit the currently accepted date.
Yes, it will be a situation of full employment for historians <g>
In any case, they will have fun looking back on the reasons they were certain about the date and deciding if those reasons are still valid, or "good" enough. It will take time for the dust to settle. Historicity is very good at this. It drove Eliade and Corbin a bit nutty in their theosophical works. I think there is an acronym that became popular... just after you have a solid train of events and explanations then one darn thing after another (ODTAA ???) comes up and you have to rework it. Historicity always wins.
Rather like water.
At least the date of the Pyramids seems a bit settled (for now <g>).