[meteorite-list] Types of twinning in chondrites?
From: Bernd V. Pauli <bernd.pauli_at_meteoritecentral.com>
Date: Sat, 22 Feb 2014 19:49:05 +0000
Jim Wooddell inquired:
"what types of crystal twinning do we see the most in OC's?"
Alan Rubin kindly posted:
"The most common type of twinning in chondrules in unmetamorphosed
chondrites is found in low-Ca clinopyroxenes. It is polysynthetic twinning
-- it looks like the pyroxene grains have narrow stripes. These disappear
when temperatures go above 630 C or so and won't be found in orthopyroxene."
Interesting additional information can be found in our late O.R. Norton's book:
=> NORTON O.R. (2008) Field Guide to Meteors and Meteorites <=
... on these pages: 217 (Figure 11.18), 228 (Figure 11.44), 241 (Minerals in Meteorites)
Received on Sat 22 Feb 2014 02:49:05 PM PST