240 Aftion tf Saline Matters eft Platina. [Book VI. 



tation, tinlefs added in very confiderable quantity. 

 Common fal ammoniac, applied to the folution of 

 platina, produces a precipitation like the .fixed vege- 

 table and volatile alkalies. It feparates a part of the 

 metal in a fparkling red powder, and a part remains 

 diffolved, which it cannot feparate ; but if vegetable 

 alkali is added after the fal ammoniac, itT precipitates 

 the reft of the platina j and on the contrary, fal am- 

 moniac, added to the folution containing the re- 

 mainder, which the fixed alkali could not feparate, 

 precipitates it, fo that by adding both the vegetable 

 alkali and fal ammoniac, the whole of the platina is 

 leparated. Platina, like gold, is alfo foluble by the 

 oxygenated muriatic acid. 



The fubtile inflammable fubftances, as fpirits of 

 wine and aromatic oils, do not produce any feparation 

 from, the folution of platina ' in aqua regia, as they do 

 from that of gold. , Tin precipitates it, but the pre- 

 cipitation is not purple like that of gold. Moft of the 

 metals precipitate platina, but it does not in general 

 fall down in the metallic ftate. The precipitation of 

 platina, from its folution by fal ammoniac, affords a 

 method of feparating this metal from the gold which 

 is mixed with it, as the gold is not feparated by the 

 addition of that fait; if, on the' contrary, we'wifh to 

 precipitate the gold, and leave the platina in iblution, 

 this may be effected by fal martis. 



The precipitates of platina may be reduced to a 

 metallic button, by heating them with the common 

 fluxes ; but thefe cannot be rendered malleable unlcfs 

 they are completely fufed, which can fcarcely be ef- 

 fected, unlefs with the heat of the moft powerful bum- 

 ing glafles. 



A mixture of copper with platina forms a metallic, 

 body Of inter mediate CQlour and 'great denfity, fo that 



