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Comparison between 2 microscopes
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Roger Warin

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PostPosted: Feb 16, 2021 15:41    Post subject: Comparison between 2 microscopes  

I would like to remind you that the examination of meteorites is also mineralogy.
The only difference, the pebbles formed in zero gravity, in the form of small silicate spheres called chondrules. There are others.
My example proposes to compare the performances of 2 Leica microscopes, one is rather a binocular, the other more suitable for petrochemicals:
The first = M125C has an apochromatic objective.
The second = DM750P is equipped with 4 lenses.
The choice of a thin section of meteorite is opportune because there is no concern with the depth of field.

In this case, since we are talking about minerals, it is olivine, always generous with beautiful colors in cross polarization.
This chondrules is called "with barred olivine". It is polysomatic.
But you should know that these olivine bars are the fruit of a very rapid crystallization (less than an hour?), of the skeletal type, like snow crystals.
Twinning of olivine can even appear whereas they are very rare in "terrestrial" mineralogy, except in gemology where some have been identified as optical defect.

I regret that this aspect of terrestrial rocks is not often presented.
PS: the meteorite is the chondrite NWA 4540 CO 3.5.

 Mineral: Olivine (Group)
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