[meteorite-list] Slickensides vs. Shock Veins correction Ringwoodite

[Mr EMan]

I am so sorry Mia Culpa!

 I was covering writing several articles tonight and
had a computer glitch along with a brain freeze.
I lost something in the process.  What I should have
said was:

"Ringwoodite" a mineral and is the spinel polymorph of
olivine. 

"Maskelynite" is not a mineral but a glass derived
from feldspars that have been shock melted.  

"Smectite" also not a mineral, is a broad term
covering  the mostly clay substance (e.g feldspar
weathering products)in terrestrial slickensides.

I suspect that the material in slickensides from
meteorites will also fall under the classification
smectite.

Thanks for paying attention!

Elton
--- dellenit at aon.at wrote:

> Hi Elton,
> 
> you are right with the slickensides. But some
> comments on Maskelynite:
> It is NOT from olivine ! it is a glassy mineral
> which has a composition of plagioclase feldspar. It
> results from quenching from shock induced melt !
> ref:
>
http://www.lpi.usra.edu/meetings/metsoc99/pdf/5047.pdf
> 
> Harald