Could this be pyroxene twinning ? (thin section)

Asked Dec 06 '16 at 18:32

Active Dec 06 '16 at 18:32

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I found this beautiful euhedral pyroxene crystal in thin section today. There is one thing that I can´t explain though.

In crossed polarizers, the crystal shows two different interference colors, which do not change as I rotate the table (no color shifting, no extinction).

As far as I know, this happens only in basal sections. But then why are there two different interference colors ? Could it be pyroxene twinning ?

Thanks for all your answers.

asked Dec 06 '16 at 18:32

Petr Hykš

5

Yes, this is a textbook example of pyroxene twinning. – Gimelist Dec 06 '16 at 20:28
for what it's worth there is a slight difference in colour in plane polarized light – haresfur Dec 06 '16 at 21:51

Could this be pyroxene twinning ? (thin section)

0 Answers0