NEW METAL FOVND IN CRUDE PLATINA. 37 



experiments, would confift of the foda-muriates of platina, of 

 palladium, and of rhodium, was warned repeatedly with fmall 

 quantities of alcohol, till it came off nearly colourlefs. There 

 remained a triple fall of rhodium, which by thefe means is freed 

 from all metallic impurities. 



(C J.) This fait, having been diflblved in a fmall quantity of Solution in 

 hot water, and let to Hand 12 hours, formed rhomboidal cryf- 

 tals, of which the acute angle was about 75°. 



(C 2.) It was then again diflblved in water, and divided into One half pre- 

 Iwo equal portions. 'Of thefe, one was decompofed by a piece cip * y Zlnc * 

 of zinc, and the other examined by the following re-agents. 



(C 3.) Sal ammoniac occafioned no precipitation; but, when The other half 



a folution of platina was added to the mixture, a precipitate was ^as precip. by 



1 f . platina, but not 



immediately formed, and the colour of this precipitate was yel- by fal-amm. 



low ; which again proves that the metal contained in this fait, 



is neither platina itfelf nor that which gives the red colour to 



its precipitates. 



(C 4.) Pruffiale of potafh occafioned no precipitation, as it nor by pr. pot- 

 would have done, if the folution had contained palladium. ' 



(C 5.) Hydro-fulphuret of ammonia, which would have pre- nor by hydro- 

 cipitated either platina or palladium, caufed no precipitation of fulph ' ofamm « 

 this metal. , 



(C 6.) The carbonates of potato, of foda, or of ammonia, nor by carb. al- 

 occafioned no precipitation ; but the pure alkalis precipitated a ' . but f ^ 

 yellow oxide, foluble by excefs of alkali, and alfo foluble in in acids. 

 every acid that I have tried. 



(D 1.) The folution of this oxide in muriatic acid, upon being Muriatic folution 

 evaporated, did not cryftallize ; the refiduum was foluble in rJlodlum ' 

 alcohol, and of a rofe colour. Sal ammoniac, nitre, or common 

 fait, caufed no precipitation from the muriatic folution; but 

 formed triple falls, which were not foluble in alcohol. 



(D 2.) The folution in nitric acid alfo did not cryftallize. A Nitric folution. 

 drop of this folution, being placed upon pure filver, occafioned 

 no ftain. On the furface of mercury a metallic film was preci- 

 pitated, but did not appear to amalgamate. The metal was 

 alfo precipitated by copper and other metals, as might be pre- 

 fumed, from the ufual order of their affinities for acids. 



(E I.) The precipitate obtained by zinc (C 2.) from the re- Theprecip. be- 



mainine half of the fait, appeared in the form of a black powder, fore mad e b y 



. ,. , • , i ^ • c , zinc was black, 



weighing, when thoroughly dried, nearly 2 grains, correspond - 



ing to about. 4 grains in the 1000 of ore diflwlved. 



(E 2.) 



