134< PHYSIOGRAPHY. 



Before the blowpipe it froths, becomes yellowish-brown, 

 and melts with effervescence into a black vesicular globule ; 

 with borax into a transparent one. It gelatinises in heated 

 acids, and according to BERZELIUS, it consists of 



Silica 32-00. 



Lime 7'84. 



Alumina 14-80. 



Oxide of Cerium 19-44. 



Protoxide of Iron 12-44. 



Oxide of Manganese 3-40. 



Yttria 3-44. 



Water 5-36. 



It occurs at Finbo near Fahlun in Sweden, along with 

 rhombohedral Quartz, prismatic Feld-spar, Albite, &c. in 

 veins traversing gneiss. 



PALLADIUM. 



METAL. 



Palladium. JAM. Sjst. Vol. III. p. 53. Native Palla- 

 dium. PRILL, p. 325. 



Grains. Octahedrons and prisms with a square 



base are quoted by SOWERBY. 

 Lustre metallic. Colour steel-grey, inclining to 



silver-white. 

 Hardness superior to wrought iron. Sp. Gr. = 11-8, 



WOLLASTON ; = 12-14, LOWKY. 



It is reducible by heat. By itself it is infusible before 

 the blowpipe, but melts with sulphur. With nitric acid it 

 yields a red solution. It consists essentially of palladium, 

 but contains also a small portion of platina and iridium. 

 It occurs along with native Platina in Brazil, and was dis- 

 covered by Dr WOLLASTOK. The pure metal is ductile 

 and very malleable ; it is flexible in thin slips, but not 

 very elastic. 



