[meteorite-list] Etching Iron Meteorites

From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Wed, 31 Jan 2007 17:42:52 -0600
Message-ID: <001d01c74591$861ed310$0de58c46_at_ATARIENGINE>

Hi, Drake,

> ...Widmanstatten patterns are unique to
> meteorites. That's not true.

    I'll bite. In what other materials can they be found?
Long considered definitive hereabouts. I quote one
source: "Widmanstatten pattern or Thompson structure:
This pattern does not appear in terrestrial iron ores.
Its presence is diagnostic in the identification of a
meteorite."
    Looking for a definition, I found that they form when
"steels are cooled at a critical rate from extremely high
temperatures. It consists of ferrite and pearlite and
has a cross-hatched appearance due to the ferrite
having formed along certain crystallographic planes."
    What's the likelihood of fake meteorites being made
that way?

Sterling K. Webb
------------------------------------------------------------
----- Original Message -----
From: "Drake" <Monel at sprynet.com>
To: <meteorite-list at meteoritecentral.com>
Sent: Wednesday, January 31, 2007 4:52 PM
Subject: Re: [meteorite-list] Etching Iron Meteorites


That was I, and thank you. The Nital I was using was what I use for
standard metallographic sample preparation at 2% to 5%. I see now I need
a much higher concentration.

I did find one metallurgical error in that it states that Widmanstatten
patterns are unique to meteorites. That's not true.

Drake

Quis Custodiet Ipsos Custodes

Drake "Doc" Damer?u
President, NEPRA
NAR Section 614
L3CC member
TRA 9934 L3

www.nepra.com
www.rocketmaterials.org
http://home.sprynet.com/~monel/home.htm




> -----Original Message-----
> From: meteorite-list-bounces at meteoritecentral.com
[mailto:meteorite-list-
> bounces at meteoritecentral.com] On Behalf Of Gary K. Foote
> Sent: Tuesday, January 30, 2007 6:21 PM
> To: meteorite-list at meteoritecentral.com
> Subject: [meteorite-list] Etching Iron Meteorites
>
> Hello List,
>
> I forget who was asking this morning, but Ruben Garcia has graciously
> allowed me to
> publish his in-depth article on cutting, etching and preserving iron
> meteorites to my
> site.
>
> For those interested the URL is;
>
> http://www.meteorite-dealers.com/etchingandpreservation.html
>
> Gary
> http://www.meteorite-dealers.com
> ______________________________________________
> Meteorite-list mailing list
> Meteorite-list at meteoritecentral.com
> http://six.pairlist.net/mailman/listinfo/meteorite-list

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Received on Wed 31 Jan 2007 06:42:52 PM PST