If both the angle of the inclined plane (𝜃) and the length of one period (x) are known, the magnitude and sign of the CR can be recovered. Taking the maximum repeating value of the CR as 0.09 radians, and extrapolating the height from zero to the first rise by the pyramidal angle (60°) the repeating linear distance between maxima is 12 µm according to Fig. . The thickness, z, along any point can be determined by applying the function ! " * tan𝜃 = 𝑧. In this way, the OR ca. 160 deg/mm is recovered, which is not an unusual value given the large spatial dispersion to be expected from a larger unit cell than that for other single crystals that have been analyzed along low symmetry directions. Solving for the sign of OR is similarly straightforward. The oscillating sawtooth profile associated with CR displays a positive or negative slope that depends on the enantiomorph. In Lcrystals the slope is alway negative (resetting instantaneously at p) with increasing z. In R-crystals the slope is always positive.