Description: A truly lucky feature of this specimen is that (100) isn't the only lateral pinacoid that's recognizably developed. Looking along the c[001] axis of the right wing (FOV 15x15mm), we can see (0 -1 0) and (1 -1 0), too! This fixes the orientation of the b[010] axis and narrows down the possibilities for a[100]. We don't yet know whether the latter is inclined upward or downward. (At any rate, it appears foreshortened in this view, and between b[010] and the projection of a[100] we see an apparent angle which is larger than the true angle gamma.) This observation determines one more sign: The composition plane must have indices (+h +2l -l) or (+h +2l +l).

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