[meteorite-list] re "How do you know it's a meteorite?"

[Dave Harris]

I get asked this question often - and I always split it in two - I say "If 
you mean ,how do I personally know it's a meteorite?'", then I reply, " 
because I purchased it from a specialist dealer/university/museum" or what 
ever...
I then rapidly follow it up with "if you mean how do _we_ as humans know it 
a space rock...?" then I briefly explain just some of the tests (isotope 
ratios, age of material & so on)

That generally satisfies most questioners of all ages it seems - not ideal 
but when a neophyte is presented with a small piece of rock the size of a 
findgernail, it is often difficult to even make them understand that the 
rock they are holding is a fragment of a larger piece - I often get asked 
"how do they find them when they're so small" for example when holding a few 
milligrams of Martian.

dave
IMCA #0092
Sec.BIMS
www.bimsociety.org