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Argentine Felfpar. 3 2 7 42d Species. f Argentine Felfpar, or Oculus Pifcis*. Its colour white, two oppofite faces filvery white, two others dead white, or yellowdh; when decompofmg iridefcent, when farther de- compofed ochre yellow. It is found amorphous in rounded iragments, or cryftallized nearly as common felfpar, or in detached plates, or in lhining ftri®. > Its internal luftre, 4. Its tranfparency, 2; or 1 when decompofing. . * Its fradture in one diredtion foliated, in anotner ftriated. . . ... Its fragments redtangular. The lamellae in flexible. . r , . Hardnefs of the filvery lamm®, 6; of the 'Qthers, 9. Brittle. Sp. gravity, when not much dccompofed, 2,500; when more advanced in this refpedt 2,300 or 2,212. When decaying, if breathed on, lt gtves an earthy fmell. _ Expofed to the blowpipe, and ftuck on glals, if the flame be diredled to the edges, it eafily melts into a clear compaä glafs; but, if the flame be diredted on the faces, they ltilL preferve thcir luftre, and only the edges üowly melt - . ,1,1 This ftone was difcovercd in the black moun- tain of Languedoc, by Mr. Dodun, one of the moft eminent French mineralogifts; by its exter-