BISMUTHIC SILVER-ORE. 59 the flux at the same time acquiring an amber colour: the metallic button is brittle, and of a tin-white colour. Constituent Parts. Bismuth, 27.00 Lead, - 33.00 Silver, 15.00 Iron, - 4.30 Copper, 0.90 Sulphur, 16.30 96.50 * Klaproth, Beit. b. ii. s. 297. Geognostic and Geographic Situations. It has hitherto been found only in the mine named Friedrich-Christian in the Schapbach, in the Black Fo rest, where it occurs in veins that traverse gneiss, along with copper-pyrites, and quartz, and a smaller quantity of iron-pyrites, and galena or lead-glance. 6. Corneous * Sell), in his Mineralogical Studies, vol. i. p. 81. states, the quantity of silver in this ore at 20 per cent.