Hi Rob, That's "rolly chair" talk....... ;) LOL
Best regards, MikeG PS - Sterling, you too! On 5/9/10, Rob Matson <mojave_meteori...@cox.net> wrote: > Hi All, > > Short opinion: manmade. > > Reasoning: the inability to produce such a form purely through > atmospheric ablation. Just to remind everyone, all of the > so-called Franconia irons are nothing more than chondritic > iron that has separated from an H-chondrite fall -- either > during flight, or by terrestrial weathering processes on the > ground. Thus it has always bothered me that these irons were > given a separate meteorite name from the ubiquitous H-chondrites > at Franconia from which they derive. If my information is > outdated on this subject, someone please let me know. But many > (most?) of the people I know who have hunted Franconia and > found these irons do not pretend that they are from a separate > iron fall -- they all accept that the iron nuggets were > spalled from an H-chondrite. > > So, getting back to Larry's unusual, tiny iron find. If this > iron did not start at the top of the atmospere as a very tiny > piece of iron, there would be no way to ablate it, let alone > punch a hole through it. Since the Franconia irons were once > part of a massive chondritic meteoroid, there was no opportunity > for these irons to experience independent, high altitude, high > velocity ablation. Their ablation history wouldn't have started > until the main H-chondrite body had fragmented on a gigantic > scale (e.g. terminal burst), which of course would have > occurred at comparatively low altitude. > > On a final note, the H-chondrite fall at Franconia was not > a recent one. While this part of NW Arizona receives little > seasonal rainfall, I don't imagine that a 0.1-gram piece of > iron could survive more than a century. But a manmade piece > of iron, dropped there in the last 50 years, might possibly > survive terrestrial weathering. > > I would love nothing more than for Larry's find to have an > extraterrestrial origin; but the physics and history of finds > at Franconia argue strongly against it. > > Best wishes, > Rob > > ______________________________________________ > Visit the Archives at > http://www.meteoritecentral.com/mailing-list-archives.html > Meteorite-list mailing list > Meteorite-list@meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > -- ------------------------------------------------------------ Mike Gilmer - Galactic Stone & Ironworks Meteorites http://www.galactic-stone.com http://www.facebook.com/galacticstone ------------------------------------------------------------ ______________________________________________ Visit the Archives at http://www.meteoritecentral.com/mailing-list-archives.html Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list