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meteorites.....
Hi all - reading this thread reminds me of when I once worked on a gang buiding small footbridges: everyone had the obligatory names; from "Ace" the foreman - who was allways fiddling with the deck(ing) down to me, aka "Rock Hunter" - the very un-Hollywood looking "go-fer" who collected the stone ballast.
Seriously though, your posts also reminded me of collecting on the Nullabor, of what we called australites: black gravel-like chips of stone that when held to strong light revealed themselves as dark green glassy material, one form of meteorite. There were also the metallic types mentioned here but they were far outnumbered by the "glassy types (or maybe these were just more easily identifiable/findable.)
I have (somewhere) a couple from those long-ago collectings; also a beautiful "basalt"(?) type one that is circular (around the size of a 20cent piece) with a convex face on one side and concave-convex on the other (ie, initially from the outside "rim" it is concave and then towards the centre has a convex profile: I was told that this is the shape it assumed whilst in a plastic state from heating as it plunged through the atmosphere. This one is approx 15mm thick.
Fascinating stuff - and apropos the cutting and etching, whilst never having worked on meteorites I possess professional/technical skills in metal-work and etching along with having been a practising jeweller for a number of years: with etching I have completed very major commissions using a variety of innovative combined techniques.
Which is to say after all the self-praise (!?!) that I would be more than happy to give anyone my two-bobs' worth should they want to discuss possibilities in these areas. I will link my web-site in the near-future to a forth-coming IIS post, where examples of my etching can be seen.
Regards, Darryl.
ps - nitric acid is usually considered too aggressive for etching ferrous materials, though the presence of nickel et al may further complicate things: but there are a number of mordants plus other techniques that are available.....
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