Dr. Wollaston on a new Metal , 
42s 
(B 2.) Of the ore thus prepared, nearly ounces were then 
dissolved in nitro-muriatic acid, (diluted for the purpose of 
leaving as much as possible of the shining powder,) and the 
whole suffered to remain in a moderate sand heat, till completely 
saturated, 
(B 3.) Such a portion of this solution was then taken for 
analysis, as corresponded to 1000 grains of the prepared ore. 
An ounce of sal ammoniac was next dissolved in hot water, 
and used for the precipitation of the platina. The precipitate 
obtained was of a yellow colour, and, upon being heated, yielded 
815 grains of purified platina. 
(B4.) The water used for washing this precipitate having 
been added to the solution poured from it, a piece of clean zinc 
was immersed in it, and suffered to remain, till there appeared to 
be no further action upon the zinc. The iron contained in the 
ore (to the amount of 14 or 15 per cent.) remained in solution. 
The other metals had subsided, in the form of a black powder, 
which I estimated between 40 and 50 grains; but, as there was 
no occasion to weigh it with accuracy, I thought it better not to 
dry this precipitate, for, if it be heated, the rhodium is in danger 
of being rendered insoluble. 
(B 5.) As I had previously ascertained that this precipitate 
would contain p'atina, rhodium, the substance called palladium, 
copper, and lead, the two last metals were first dissolved in 
very dilute nitric acid, aided by a gentle heat. The remainder, 
after being washed, was digested in dilute nitro-muriatic acid, 
which dissolved the greater part, but left as much as 4^ grains 
undissolved.* 
* It was presumed that this residuum consisted principally of the metal called by 
Mr. Tennant Iridium; but, as it was accidentally mislaid, and was not examined, 
it might also contain a portion of rhodium. 
