Aggregates. Rragg Porphyry. See Lelke S. 1078, 107 9 S93, and 941. Greyifh red, or dark purplifh red. Luflre, and tranfparency, o. Exceedingly porous. Fradture, uneven and earthy. Hardnefs, from 5 to 7. Feels rough and harlh; gives a yellowifli grey, or reddifh flreak. 1t often verges to fandftone. Argillitic Porphyry. This is diftinguilhable from the foregoing not merely by its flaty fradture, but aMo generally by its luftre; and ofren by its flight tranfparency. It is found in the ßobroulki Mountains. Reno- ranz 5, Novaculite Porphyry. Greenifh grey, or greyilh yellow. Luftre, o. Tranfparency, 1 1,5. Fradture, fine fplintcry, earthy, or flightly conchoidal; but, in the grols, often flaty. Hardnefs, from 7 to 8, rarely 9. Feels fomevvhat greafy. Muriatic Pcrphyries. Thefe have either potflone or I’erpentine, for their bafis. 3 Poteßon
