A tanzanite displayed crystallographically aligned, vividly iridescent colors resulting from fine separations along the stone’s cleavage planes.

The first visual record of axinite inclusions in quartz published in the gemological literature.

A spinel from Madagascar, mixed in with a parcel of blue sapphire, exhibited an array of internal features.

This violet-colored fluorite crystal was free to move in its octahedral void, as seen in four different positions. Photomicrographs by Nathan Renfro; field of view 7.18 mm.