[meteorite-list] Sahara sand
From: Dave Mouat <dmouat_at_meteoritecentral.com>
Date: Thu Apr 22 09:52:06 2004 Message-ID: <3D4EEFC5.4B5CE9E0_at_dri.edu> --------------C1244F4126E46A393F17D99D Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I hope this finds the sender. Much of the world's sandy deserts are reddish. Usually, the redder sands indicate somewhat older dunes. The dunes of Namibia may be over 20 million years old. Whoops, off the subject. The redness does imply iron staining with the total iron content less than 1%. Little black specks are most likely magnetite but could be micro meteorites. The rest of the material (yawn) is most likely quartz. Dave MuseumStore/NatureSource wrote: > (I tried to post this yesterday, but didn't see it come up. Sorry if > it's a repeat!) Hi List! > Can anyone tell me anything about the general composition of Sahara > Desert sand? I have a couple vials that I've been looking at on my > lunch break. Just out of curiosity, I held a Nd magnet against the > glass of the vial and several little black specks jumped up on to the > magnet. I looked at them under a binocular microscope. I couldn't > rule them in or out as little micrometeorites. The orange color of the > sand leads me to believe that iron may be a factor in the sand's > coloration and composition, and that these specks may just be ferrous > minerals and nothing to get too excited about. Has anyone come across > this? Does anyone have any > information/thoughts/comments? Regards,Jeanne DevonIMCA > #9236www.thenaturesource.comThe Museum Store/The Nature Source --------------C1244F4126E46A393F17D99D Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit <!doctype html public "-//w3c//dtd html 4.0 transitional//en"> <html> <body bgcolor="#FFFFFF"> I hope this finds the sender. <br>Much of the world's sandy deserts are reddish. Usually, the redder sands indicate somewhat older dunes. The dunes of Namibia may be over 20 million years old. Whoops, off the subject. <br>The redness does imply iron staining with the total iron content less than 1%. Little black specks are most likely magnetite but could be micro meteorites. <br>The rest of the material (yawn) is most likely quartz. <br>Dave <p>MuseumStore/NatureSource wrote: <blockquote TYPE=CITE> <font color="#000000"><font size=-1>(I tried to post this yesterday, but didn't see it come up. Sorry if it's a repeat!)</font></font> <font face="Arial"><font size=-1>Hi List!</font></font> <br> <font color="#000000"><font size=-1>Can anyone tell me anything about the general composition of Sahara Desert sand? I have a couple vials that I've been looking at on my lunch break. Just out of curiosity, I held a Nd magnet against the glass of the vial and several little black specks jumped up on to the magnet. I looked at them under a binocular microscope. I couldn't rule them in or out as little micrometeorites.</font></font> <font color="#000000"><font size=-1>The orange color of the sand leads me to believe that iron may be a factor in the sand's coloration and composition, and that these specks may just be ferrous minerals and nothing to get too excited about.</font></font> <font size=-1>Has anyone come across this? Does anyone have any information/thoughts/comments?</font> <font size=-1>Regards,</font><font size=-1>Jeanne Devon</font><font size=-1>IMCA #9236</font><font size=-1><a href="http://www.thenaturesource.com">www.thenaturesource.com</a></font><font color="#000000"><font size=-1>The Museum Store/The Nature Source</font></font> </blockquote> </body> </html> --------------C1244F4126E46A393F17D99D-- Received on Mon 05 Aug 2002 05:36:05 PM PDT |
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