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To: Ahban

I heard a radio-net program that has bearing on this. Apparently they are using biolumenescence [sic] to date these tools.

Through diligent research I have discovered that bioluminescence pertains to the production of light by living organisms and has nothing to do with dating techniques.  Doing a search on dating techniques did reveal a technique referred to as Luminescence Dating.

From Luminescence Dating at the Research Laboratory for Archaeology and the History of Art:

The typical age range for luminescence dating is ca.10 years to 300,000 years (though this is highly sample dependent). The uncertainty on luminescence dates is typically in the range of ± 5% to ± 12% of the sample age.

Luminescence dating is particularly useful when radiocarbon dating is not possible. This would be the case, for example, when organic material has not been preserved or when the relationship between the organic material and the archaeological context cannot be confidently assumed. Further, luminescence dating may also be of help when the age of the sample is greater than the 40-50,000 year limit of radiocarbon dating.

Junior, It is pretty new info. There was a radio program with a lot of on it one month ago. It is archived here...

It is evidently so new that the various journals pertaining to dating techniques make no mention of it at all.  Luminescence Dating has a history going back three decades and has been refined to high accuracy over that time.

Also, there is no mention in any of the literature that Luminescence Dating only gives a maximum date value; rather it gives a date from the last time the object was exposed to sunlight.  From the source above:

In order for luminescence dating to be successful, sediment samples (for OSL dating) must have been exposed to sunlight immediately prior to deposition, such as would normally be expected to have occurred during transport by either water or wind. Pottery and burnt flint must have been heated to at least 400° C. The pottery and flint samples must be sufficiently large so that, after removal of a 2mm layer from each surface, a fragment whose volume is equivalent to at least 1cm x 2cm x 3cm remains. In addition, as an absolute minimum, it is essential to provide a sample of the soil (at least 50g) in which the pottery or flint was buried (see Sample Collection for further details).

And also:

Sediment dating requires specialised sampling procedures in which metal cylinders are driven into the sediment to be dated. Following removal of the sample tube it is desirable to measure the environmental radiation dose rate using a portable gamma spectrometer.

No special techniques are involved in the collection of pottery or burnt flint samples although exposure to light and heat should be kept to a minimum. On site measurements of the environmental radiation dose are also desirable, especially in the case of burnt flint dating. When on-site measurement of the environmental radiation dose is not possible, soil samples representative of the deposits (up to a distance of 30cm around the pottery or flint) must be collected. In these circumstances it is highly desirable that these deposits are as uniform as possible and that pottery or flint are not collected from near sediment boundaries (edges of pit or changes in sediment type) or large boulders.

If your source really did call the dating technique used "bioluminescence" (I have not listened to the audio file as I have not had time to do so) then he has demonstrated his ignorance of dating techniques and his conclusions may be called into question.

As for your contention that the finding of 60,000 years for human remains in Australia has been falsified by more recent findings:

For example, a find in Austraila [sic] recently shocked the world with a biolum date of 60K years old. New data (they found a way to carbon date this find) now supports a date of from 1-3K years.

According to Mungo Man older than thought, 60,000 year figure was not arrived at only through Luminescence Dating, but also through uranium series dating (which can be used to date finds up to 70,000 years old) and electron spin resonance dating.  These figures were independently verified (as are all datings) by another institution:

Cross-matching a range of recent dating tests puts the minimum date of the burial of the remains at 56,000 to 68,000 years ago. The research, to be published today in the Journal of Human Evolution, came up with almost identical dates.

An analysis of his mitochondrial DNA (and hence, his relationship to other humans) is mentioned in the article, Mungo Man vs. Mitochondrial Eve.

I have not found any references to these remains being redated to only 3000 years old; the latest article referenced on this subject was dated 9 January 2001.  If there has been any redating of these finds, it had to have occurred this year and not yet be common knowledge (though, with all the hype associated with the 60,000 year figure, any refutation of that date would make front-page news).  Once more, I think your Dr. Ross is terribly mistaken in his reporting and his reports should be scrutinized more carefully.

13 posted on 12/04/2001 6:15:21 AM PST by Junior
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To: Junior
Junior, I was just trying to answer your request for info. It was a brain slip on my part to put the "bio" in front of the lumen in my prior post. Dr. Ross does not call it that, I did in an honest slip up.

You say Mungo man was dated in the 60-70K range with uranium series dating. I am pretty sure that uranium has a trendously long half life, which makes it 'bout useless for dating stuff 60K (or less).

You might at least listen to the link I went to the trouble to find for you at your request before you dismiss it out of hand.

Ahban

14 posted on 12/04/2001 12:57:20 PM PST by Ahban
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