FMF Minerals Gallery

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Close-up looking at the inclusions - as far as I can tell, there’s both galena (the lustrous octahedra) and sphalerite (the rougher shapeless grains) among them. At this magnification (FOV 10.9x18.1mm), it becomes obvious that they sit on an otherwise almost invisible interior phantom which is mostly octahedral, except the corner pointing towards us is truncated by a small cube face, oriented the same way as the one through which we’re looking. (Author: Gerhard Niklasch)