Before I speculate any further, Bob - can you please elaborate what is the device used to analyse the data?
Is the coin removed from the slab or you can use the spectrometer to analyze any coins in any slab?
My partial coin collection
http://www.omnicoin.com/collection/gxseriesMy numismatics articles and collection:
http://www.gxseries.com/numis/numis_index.htmRegularly updated at least once a month.