Jüngsten, 133 Luftre, 2»—Tranfparency, 0.—Fra&ure, un- even, granulär, and partially fplintery, fometimes flaty.—Hardnefs, 8.—Sp. gr. 5,570.—Gives a powder of an ifabella yellow colour. According to Mr. Klaprotb, it contains 88 per ct. of tungftenic acid, 11,5 of pure calx, and £ a grain of argill and calx ofiron. Note. The red or flefh-colured ftone of Ryt- terfhutte, which with Cronfted Ifufpedfed to con» tain the tungftenic acid, is now found to confift only of calx, 24 per ct. of iron, and of filex 22, See Ferricalcites. Thisfpecies may perhaps morejuftly be confi- dered as an ore of tungftenical fubftance, of which jvc lhall treat in the 4th part of this work. SEC-