Platinum, . . . . . 76.4 Iridium,. . . . . . 4.3 Rhodium,. . . . . . 0.3 Palladium,. . . . . 1.4 Gold, . . . . . . . 0.4 Copper, . . . . . . 4.1 Iron, . . . . . . . 11.7 Osmide of Iridium,. 0.5 Sand, . . . . . . . 1.4 ————— 100.5 This refers to the Uralian ore. In that state of combination, as shewn in the table, the iridium and osmium are found combined in crystals, sometimes to the amount of 0.5 per cent., and sometimes 3 or 4 per cent. Now, this Deville proposes to deal with in the dry way, in the place of dealing with it by any acid. I have here another kind of platinum; and I shew it to you for this reason. The Russian Government, having large stores of platinum in their dominions, have obtained it in a metallic state, and worked it into coin. The coin I have in my hand is a twelve silver rouble piece. The rouble is worth three shillings, and this coin is, therefore, of the value of thirty-six shillings. The smaller coin is worth half that sum; and the other, half of that. The metal, however, is unfit for coinage. When you have the two metals, gold and silver, used for coinage, you have a little confusion in the value of the two in the market; but when you have three precious metals (for you may call platinum a precious metal) worked into coin, they will be sure to run counter to one another. Indeed, the case did happen, that the price of platinum coin fixed by the Government was such, that it was worth while to purchase platinum in other countries, and make coin of it, and then take it into that country and circulate it. The result was, that the Russian Government stopped the issue. The composition of this coin is—platinum, 97.0; iridium, 1.2; rhodium, 0.5; palladium, 0.25; a little copper, and a little iron. It is, in fact, bad platinum: it scales, and it has an unfitness for commercial use and in the laboratory, which the other well-purified platinum has not. It wants working over again.