6 PALLADIUM. 2. Palladium. Palladium, Wollaston, Philosophical Transactions for 1809, p. 192. External Characters. Its colour is pale steel-grey, passing into silver-white. It occurs in small grains. The lustre is metallic. The fracture is diverging fibrous. It is opaque. Specific gravity, 11.8, 12.148*, Wollaston. Chemical Characters. It is infusible; but on the addition of sulphur, it melts with ease ; by continuance of the heat, the sulphur is- dissipated, and a globule of malleable palladium remains. It forms a deep red solution with nitric acid. Constituent Earls. It consists of Palladium, alloyed with a minute portion" of Platina, and of Iridium. Geognostic and Geographic Situations. It is found in grains, along with grains of native pla'- tina, in the alluvial gold districts in Brazil. Observations. This mineral was first discovered, described, and ana lysed by Dr Wollaston. „ 3 Iridium. ....... ■— . . -■ — —- ■— T ■ * The second specific gravity was communicated to me by Mr Lowry.