SILESIAN EARTH, in the Materia Medica, a fine astrigent bole. It is very heavy, of a firm compact texture, and in colour of a brownish yellow. It breaks easily between the fingers, and does not stain the hands; is naturally of a smooth surface, is readily diffusible in water, and melts freely into a butter-like substance in the mouth. It leaves no grittiness between the teeth, and does not ferment with acids. It is found in the perpendicular fissures of rocks near the gold mines in Hungary.