NATIVE PLATINUM. 



Analysis, from the Pinto, by Svanberg 



Platinum 



. 84-34 



Palladium . 



. 1-66 



Khodium 



. 3-33 



Iridium 



. 2-58 



Osmium 



. 0-19 



Iron . . . . 



. 7-52 



Manganese . 



. 0-31 



Osmium -iridium . 



. 1-56 



Copper . . . . 



. trace 



101-29 



BB infusible. 



Soluble in heated nitro-muriatic acid only. 



Localities. Irish. — The auriferous sands 

 of some of the rivers in Wicklow. — Foreign. 

 New Granada : in the province of Choco, at 

 the lavaderos, or gold washings of Barba- 

 <;oas and in the weathered syenite near Sta. 

 Kosa de Osos, in the province of Antio- 

 quia, in Colombia. In the provinces of 

 Mato Grosso and Minas Geraes, in Brazil. 

 Hayti. Borneo. The north of Ava. The 

 gold-sand of the Rhine. Confolens, Al- 

 loue, Epe'ne'de, Planveille, and Melle, in 

 the Depts. Charente and Deux-Sevres, in 

 France. In silver-ore from Guadalcanal 

 in Spain. Rutherford county, North Caro- 

 lina. St. Francois Beauce, Canada East. 

 California. Oregon. Australia. In drift or 

 alluvium at Nijne Taguilsk, and Goroblago- 

 dat in the Ural. 



Name. From platina, the Spanish diminu- 

 tive for plata (silver). 



Brit. Mus., Case 2. 



M. P. G. Principal Floor, Wall-case 23. 



Platinum is a useful metal on account of 

 its hardness, infusibility, and the resistance 

 which it offers to the action of air and mois- 

 ture. It has been coined in Russia into 

 pieces of eleven and twenty-two roubles 

 each. Its principal use, however, is as a 

 material for chemical vessels and crucibles, 

 for which it possesses the advantages over 

 other metals of withstanding oxidation at 

 a red heat, of not being attacked by sulphur 

 or mercur}', and of not dissolving in any 

 simple acid. It is the most ductile of the 

 metals after gold and silver, and may be 

 drawn out into wire — i— of an inch in dia- 

 meter ; and if enclosed within a silver wire 

 it may be reduced to \^ and even to ^ — 



•^ 5000 20000 



of an inch in diameter. It may also be 

 beaten out into very thin laminae, like gold- 

 leaf. It exceeds all metals in tenacity, ex- 

 cept iron and copper. It may be welded at 

 a white heat. 



Platinum is also used for covering other 

 metals, for painting on porcelain, &c. 



NATIVE SILVER. 253 



Native Prussian Blue, or Blue Iron 

 Earth. A variety of Vivianite. 



Native Quicksilver. Cubical. Occurs 

 in small globules disseminated through its 

 matrix. Colour silver-white. Lustre me- 

 tallic. Opaque. Fluid. Freezes at — 39-44°. 

 Boils at 662° F. S.G. 13-568, 



Comp. Pure Mercury or Hg ; sometimes 

 with a little silver. j> 



BB volatilizes entirely. 



Readily dissolves in nitric acid. 



Localities. Chiefly at Almaden in Spain, 

 and Idria in Carniola. Wolfstein and 

 Morsfield in the Palatinate. Carinthia. 

 Hungar^^ France ; at AUemont in Dau- 

 phine, and Peyrat le Chateau, Dept. of the 

 Haute Vienne. Peru. California. 



Brit. Mus., Case 2. 



3L P. G. Principal Floor, Wall-case 23. 



Cinnabar is a rave mineral, and most of 

 the quicksilver of commerce is obtained from 

 it. Quicksilver is used for a great variety 

 of purposes, in the process of daguerreotyp- 

 ing, in pharmaceutical and chemical pre- 

 parations, in the manufacture of fulminating 

 powder for percussion caps, for thermome- 

 ters and barometers, for silvering mirrors, 

 in the amalgamation of gold and silver ores, 

 &c. &e. 



Name. The name Quicksilver, or live silver 

 (Argentum vivum), has reference to its ex- 

 treme mobility, and its resemblance in colour 

 to silver. 



Native Red Iron Vitriol of Fahlun, 

 Haidinger. See Botryogene. 



Native Selenium has been observed by 

 Del Rio, at Culebras, in Mexico, forming 

 greyish- or brownish - black incrustations, 

 which are translucent, and appear red, in 

 thin splinters, by transmitted light. H.2. 

 S.G. 4-3. 



According to Mons. Raphael Napoli, Pro- 

 fessor of Chemistry at Naples, pure Sele- 

 nium is deposited in the cavities and crevices 

 of the lava of Vesuvius, as well as in the in- 

 terior of the solidified mass. 



Native Silver. Cubical. Occurs crys- 

 tallized in cubes and octahedrons. Cleavage 

 none; also capillarj^ ramose, reticulated, 

 in plates and superficial coatings, and mas- 

 sive. Colour and streak silver-Avhite, but 

 generally tarnished yellowish-brown or grey- 

 ish-black. Lustre metallic. Opaque. Flex- 

 ible. Ductile. Malleable. Fracture fine- 

 hackly. H. 2o to 8. S.G. 10-0 to IPl. 



Comp. Silver, or Ag, with copper, gold, 

 platinum, &c. 



BB fuses, and crystallizes on cooling. 



