BOLE

an earthy mineral which occurs in amorphous ma es, and is composed chiefly of silica vnth up about 20 per cent, of alumina and 10 of iron. It is 40 of a dull yellow, brownish, or red colour, has a greasy feel, and yields to the naiL It has a oonchoidal fracture; its streak is shining, and it is opaque or slightly translucent. It is found in various localities, such as Armenia, Saxony, Tuscany, and the isle of Skye in Scotland. In ancient times, under the name of Lemnian bole or earth, it had a place in the mater i a medic a, but is no longer used. At present the only bole of commerce is a coarse pigment sold under the name of Berlin and English red. 271