-=> Quoting Jack Sargeant to Michael Tauson <=-
 > (carbon, chromium, et al) and isotopes of iron (and the others,
 > of course) consistant with their occurance in nature on the world
 > on which that ashtray was made.
 JS> So what you are saying is, even if the "alien ashtray" were made of
 JS> similar metals found here on earth, we could tell that it was
 JS> "unearthly" in origin?
     I can only think of two cases where this would fail to give 
such evidence.  First, if the sample were made from ores that had 
a unusual isotropic ratios, or if the isotope ratios were 
intentionally distorted.  In the first case, while it would not 
be impossible for all the material involved to be distorted, it 
would be highly improbable and obtaining additional samples would 
help.  In the second, it would be unlikely that this would be 
done since the only real purpose to doing so would be to throw 
off folks like us  and, while I know practically nothing about 
metallurgy, I suspect it would neither be inexpensive nor easy to 
accomplish. 
     Again, I have to add the caveat that this is from what I 
remember of that conversation and it is my recollection that that 
was the conclusion of it.
Michael
... Speed doesn't kill, running into slow things kills.
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