Saddle dolomite crystals are composed of subcrystals that are slightly overlapped, rotated, and tilted with respect to each other. The subcrystal arrangement resembles a screw-like pattern. The c axes of subcrystals are skew lines: their directions change from horizontal to steeply inclined relative to the substrate. In thin section the traces of the c axes of subcrystals simulate a divergent (or convergent) pattern, which is the cause of sweeping extinction typical of saddle dolomite.

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