A piece of moon rock is for sale at a , with bids starting at USD $50 000. At the time of writing, no-one seems game to put down the money for a 5kg chunk of rock geologically and chemically identical to a $1 piece of Arizonian desert boulder.
Then again, diamond dealers are also so concerned with as to reject the creation of Cd via any process other than slow geological . Both enterprises sound like artificially inflated markets to me (though the lot does include a rather nice from the good folks at NASA - there's a bit of a story behind this rock, after all).