$26 , CALC GENUS. Obfervation. It has been conjedfured to be disintegrated, indu* rated marie ; but of this we have no proof. Vid. Brq- (hant. Geographic Situation. Is found in Thuringia. SESOND SUBSPECIES. f Indurated Marie. 1 External Charaders. Smoke grey, and fometimes yellowilh grey. Occurs maflive. Luflre dull, and fometiines glimmering, which latter is owing to an admixture of foreign particles- Fra&ure commonly earthy, fometimes fplintery, ° r imperfeftly flaty. Fragments