Hi Out There

I remember, through reading a book, a paper, material on the net or
through discussion with others, coming across a principle upon which
you may be able to tell if this Pb had came from a specific region.
The isotopic ratio of lead can be an indication of where this Pb
originated from, Australia, the US or other mining ores. However, I
cannot find a reference on this. If you can expand on this subject or
know of a reference about it, I would be grateful.

Many thanks
Ahmed
Dr Ahmed Ayoub
Analytical Group
Macaulay Land Use Research Institute
Craigiebuckler
Aberdeen AB15 8QH
U.K.