NEW METAL FOUND IN CRUDE PLATINA. 



(E 2.) When expofed to heat, this powder continued black ; 

 with borax, it acquired a white metallic luftre, but appeared 

 infufible by an) degree of heat. 

 fufiblewith (E :i.) With arfenic, however, it is, like platina, rendered 



md with f u fib| e . an( ^ m^ e palladium, it may alfo be fufed by means of 

 fulphur. The arfenic, or the fulphur, maj be expelled from 

 it by a continuance of the heat; but the metallic button ob- 

 tained does not become malleable, as either of the preceding 

 would be rendered by fimilar treatment. 



(E 4-.) It unites readily with all metals (hat have been tried, 

 excepting mercury ; and, with gold or filver it forms very mal- 

 leable alloys, thai are not oxidated by a high degree of heat, 

 but become inciufted with a black oxide, when very flowly 

 cooled. 



(E 5.) When 4 parts of gold are united with one of rhodium, 

 although the alloy may aflume a rounded form under the 

 blowpipe, yet it feems to be more in the ftate of an amalgam 

 than in complete fufioni 



(E 6.) When fix parts of gold are alloyed with one of rho- 

 dium, the compound may be perfectly fufed, but requires far 

 more heat than fine gold. There is no circumftance in which 

 rhodium differs more from platina, than in the colour of this 

 alloy, which might be taken for fine gold, by any one who is 

 not very much accuftomed to discriminate the different qualities 

 of gold. On the contrary, the colour of an alloy containing 

 the fame proportion of platina, differs but little from that of 

 platina. This was originally obferved by Dr. Lewis. " The 

 " colour was ftill fo dull and pale, that the compound (five 

 '* to one) could lcarcely be judged by the eye to contain any 

 gold."* 



I find that palladium refembles platina, in this property of 

 defiroying the colour of a large quantify of gold. When one 

 part of palladium is united to .fix of gold, the alloy is nearly 

 white. 



(E 7.) When I endeavoured to diffolve an alloy of filver or 



by'combkation! °^ K ^ w' 1 ' 1 rhodium, the rhodium remained untouched by 



either nitric or nitro-muriatic acids ; and, when rhodium had 



been fufed with arfenic or with fulphur, or when merely heated 



by itfelf, it was reduced to the fame ftate of infolubility. But, 



fni.ply heated, 



IV] cL: 



not mailable, 



unites with 

 c i a scep1 

 mercury. 



GoU and rhodi 

 um 4 to i. 



Gold and rho- 

 dium 6 to one. 



It do~s not dif- 

 colour gold. 



Solubility of 

 rhodium affected 



* Lewis's Philofophica! Commerce of Arts, p, 526. 



'hen 



