Litbomarga. In Saxony this earth commonly lies under jmould ; in England under fandftone or fand, and over fandftone orlimeftone; in Germany it has alfo been often found fofituated; fometimes too in the neighbourhood of Trap, or Bafalt. x Berl. Beobacht, 21. 4th Tribe. The finer Clays in various States of Induration. xft Family. Lithomarga. Steinmarck of the Germans. Thefe earths are principally diftinguiflied by their great finenefs, and fufibility into a frothy flagg* ift Variety. The friable or crumbling kind. Colour, white, or yellowifli, or rcddifh white. Euflre, x or o. Tranfparency, o. Seldom loofe, moft commonly moderately co- herent, and formed of fcaly or cxceeding fine particles, and then adheres ftrongly to the tongue. Scarcely flains the fingers. Feels very fmooth. Aflumes a polifli by fridtion with the nail, Fra&ure,