...as opposed to meteorites! Every week I receive at least half a dozen e-mails from hopeful correspondents who think they've found a 'genuine meteorite'. They rarely put it in those terms, of course: they are frequently very sure of themselves to the point of abruptness. A typical e-mail would read:
"I found this meteorite on my drive / the beach / while walking the dog. I know it's a meteorite because it's attracted to a magnet / is nothing like I've seen before / it looks like the ones on your website. Would you like to make a sensible offer for it?"
In the thirty or so years I've been selling and lecturing about meteorites only a single person has ever shown me the real article: the other (several thousand!) have mostly been one or other of those in the image below:
1) Marcasite: an iron sulphide mineral that occurs in lumpy, spherical nodules in chalk or limestone regions
2) Slag: Back in the middle ages many communities had small-scale iron smelters: the glassy residue is a common sight even on country walks. With the advent of the railways, furnace slag was frequently used for rail beds.
3) Belemnite: The internal skeleton of these squidlike cephalopod molluscs are one of the most common mesozoic fossils: even in recent times they were often called 'thunderbolts'.
4) Haematite: This iron oxide ore can occur in lustrous, mammiform (look it up!) lumps.
5) Magnetite: Another iron oxide mineral: this is the only one of the above that is attracted to a magnet.
The 'killer' is that almost all meteorites test positively for nickel, which none of the meteorwrongs above do.
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