[meteorite-list] Opinions wanted on an NWA

From: E. L. Jones <jonee_at_meteoritecentral.com>
Date: Fri Feb 11 03:52:50 2005
Message-ID: <420C725C.5080906_at_epix.net>

Hello Darren,

The low number of chondrules indicates a 5 or 6 IMHO. I wouldn't rule
out "H" as H is not just free metal but overall metal content amongst
other things. Outwardly the color of the matrix looks more like olivine.

The black veins are probably a dark purple if you look closely. It is
most probably Ringwoodite. Ringwoodite is a high pressure (spinel
form)of olivine(Forsterite/Fayalite). Ringwoodite has only been
physically observed in meteorites. Its presence in the deep mantle is
indicated by earthquake wave transmission properties.

Ringwoodite is formed in high speed collisions. Some of the clasts may
distorted chondrules. The round blebs of iron appear to be remelts.
Both occurances then to back this up.

Did you note the green object in the 10 to 11 o'clock position? Looks
alot like an large sheared olivine chondrule and not impossible that it
is a relic olivine crystal.

Elton

Darren Garrison wrote:

> There are few if any visible chondrules and a small number of clasts.
>(snip) and has a tracery of tiny black veins and tiny black "pockets"
throughout.

> Any ideas as to "casual" classification? I'm sure that it isn't an
> "H", but does the absence of noticable chondrules/presence of black
> veins signify shock melting?
>
>
Received on Fri 11 Feb 2005 03:52:44 AM PST