Fig. 1. A. A in Comparison of exposure ages and spectral properties of rock surfaces in steep, high alpine rock walls of Aiguille du Midi, France

Fig. 1. A. A slab from Maysville, KY (CMC IP50706) with a drilled specimen of the stylophoran mitrate Enoploura popei Caster, 1952. The hole indicated by an arrow. B. Close up of the drilled specimen. C. Detail of the borehole.