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What is a thin section? What do all the colors mean?
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Thin section. H-metal
TKW 52.3 grams. Fall not observed. Found 18 May 2004, in Mojave County, Arizona, USA.
Laurence writes:
Reflected-light view of a Franconia-Sacramento Wash 005 metal nodule (23.18 g, found by Mike Miller and acquired by ASU). Field of view 0.6 x 0.4 mm. Sample is polished and then etched/stained with sodium bisulfite. This chemical stains the kamacite, but not the other phases. In this image, kamacite is blue-reddish-brownish. The color of staining is in part dictated by the orientation of the metal grain, so the Neumann bands show a different color than the host grain. Other phases include: bright white - taenite, bright white with mottled dark core - taenite with plessite, grey euhedral - chromite, light yellowish cream - troilite, copper color - copper.
Note, the whole naming of the meteorites in and around the Franconia area is far from clear - hence the creation of the Yucca dense collection area (DCA) name. However, the use of the Yucca XXX DCA numbering scheme just hides the problem of how the various finds in this area may or may not be related. The metal nodule pictured here matches the description of SaW 005 in the meteoritical bulletin database, and in the paper by Devin Schrader - "Sulfide-rich metallic impact melts from chondritic parent bodies", Meteoritics & Planetary Science 45, Nr 5, 743–758 (2010).
Center for Meteorite Studies at ASU |
Click to view larger photos #1
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Found at the arrow (green or red) on the map below
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Unclassified Stewart Valley |
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Michael Mulgrew |
This Month
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John Cabassi 1/18/2014 7:23:21 AM |
Fantastic Laurence. Had the pleasure of inspecting Jim Smallers 43.7 (RIP Jim)
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Mirko Graul 1/18/2014 5:07:58 AM |
Very nice, Laurence! |
http://tinyurl.com/k69olmz 1/18/2014 3:41:01 AM |
For a description of the various chondrites that are the source of these numerous metal nodules from the Yucca DCA, read here: Stones from Mohave County, Arizona - Multiple falls in the *Franconia strewn field* by Melinda Hutson, et al. |
Ian Macleod 1/18/2014 2:13:46 AM |
Beautiful image! Thank you for the description of the materials that are in this meteorite.
I have a few Yucca XXX they all look so similar to me, they are all small fragments. |
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