Crystal morphology of spinel from Mogok, Myanmar

-Especially the hexagram-

Abstract

The crystal morphology of spinel called hexagram, found in Mogok, Myanmar, can be of two types: twins and triplets. Both exhibit pseudotrigonal crystal morphologies, and unlike the conventional parallel contact spinel-type twins and triplets and the mirror contact twins that are Otani-type triplets, these are contact twins with a rotational element.

We propose to name these morphologies as o-plane contact twins and triplets with a center of symmetry, i.e., involving rotation, or simply Mogok-style twins and triplets.