On 03 Jan 98, concerning _Skeptic's corner._, George Jiri Opletal said to 
Troy H. Cheek in UFO:
 TC>> found in 98% of the sample and the isotope with 18 neutrons that's
 TC>> found in 2%, then we can also extract enough of the second isotope
 TC>> to dope another specimen with so that it's 90%/10%.
 GJO> 
 GJO> Ok...like enriching uranium to weapon grade material.....
Yeah, that was my original example, though it got lost in the repeated 
quoting.
 GJO> Indeed this would tell you the difference between natural and 
constructed
 GJO> materials, but between human and Extraterrestrial?  I am not sure...
Some people tell me that if the ratio between isotopes in a particular 
element are pretty much constant all around the world, even in manufactured 
products, then finding a manufactured product with the isotope ratio 
completely out of whack for Earth (or our solar system) would indicate that 
said product must have been manufactured on another planet (or in another 
solar system).  I.e. we can tell the difference between widgets made in 
Taiwan and widgets made in the Crab Nebula.  I disagree because I figure if 
we can detect said isotope ratios, we can also (with a great deal more 
effort, of course) manipulate said isotope ratios.
Which pretty much recaps how I got dragged into this conversation to begin 
with.
:-)
... The best defense against logic is stupidity.
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