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If you look at the photograph, you will notice that the crinoids are slightly deformed. In case of Pentacrinus, the angle of 72 degrees gets altered.

Adjacent is an image of jasperized Carboniferous crinoids in a low grade marble from a major Tertiary shear zone in western Spitsbergen. Careful inspection shows how they are deformed into natural ellipses. The low-angle diagonal subvertical surface is a solution cleavage, while the concentration of crinoid fragments is on a sub-horizontal bedding surface. Since the yellow carbonate matrix and the red jasperized crinoids are composed of different minerals they have different strengths, with the matrix being weaker. The crinoid ellipses thus represent a minimum strain the bulk rock has seen. A tip of a swiss army knife blade is in the lower center for scale.