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[Bob Morgan]

Last year in Tucson I got a quartz from Kara Oba with fluorite from Crystal Classics - not near as pretty.
It turned out to be a most remarkable Reichenstein-Grieserntal Law twin, and, because it was a floater, it was doubly terminated showing both angles associated with that twin law.

I'm seeking more information on Kara Oba. Since R-G Law twins are nearly always associated with Japan Law twins, are any Japan Law twins from there?

The twin is a 'y' twin from an oriented attachment of a smaller crystal on the larger one.

The first photo is taken perpendicular. straight out from the twin showing parallel 'r' faces on the outsides of the twin. They would extend out from the screen. The angle toward the top is the Grieserntal 76 degree angle. The one toward the bottom is the Reichenstein 103 degree angle.

The second photo highlights the parallel 'r' faces across the Reichenstein angle.