The three photomicrographs below show glassy pumice with fluorite in vesicles (SLIDE 63, from a small pit south of the Blue Chalk prospect), sericite rimming a rock fragment (SLIDE 64, from the Roadside pit), and potassium feldspar overgrowths on sanidine (SLIDE 65, from the Roadside pit); the scale bar in the lower right is 0.2 mm. The three photomicrographs correspond to the glassy, argillic, and feldapathic alteration facies described in the beryllium tuff by Lindsey and others (1973).
