soil
What is seen the interference colour?
The interference colour is observed under the petrographic microscope with the analyser incorporated (in crossed-polarised light, XPL) and with parallel light (without the condenser).
rock
soil
Sometimes the minerals have an abnormal color that does not correspond to their birefringence.
A typical example of an abnormal interference color is chlorite.
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| XPL.Chlorite abnormal interference color: Blue | PPL. Chlorite natural color: green |
Most often, the abnormal interference color is due to the mineral's own natural color. This occurs whenever the mineral has an intense natural color.
A typical example is biotite.
Also other minerals present anomalous interference colors.
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Index | Introduction | PPL | XPL ortos | Interference colour | Previous | Next