Tiny guest oriented inclusions with biotite crystal inclusions in a peridot (forsterite) from Myanmar
One of you asked us the question we were expecting (publication February 24th 2020 on Instagram) about the following micrograph of peridot (forsterite):
"What are the short black needles in the photo?"
In fact, these are not needle-like crystals like rutile or hematite-ilmenite which are found in corundum for example.
They are simply very fine flat biotite crystals that are observed parallel to their plane and which, consequently, look like needles on a micrograph.
Figure 1: Inclusions of biotite from Pyaung Gaung, Mogok, Myanmar, observed parallel to their plane.
Figure 2: Inclusions of biotite from Pyaung Gaung, Mogok, Myanmar, observed perpendicular to their plane.
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