Gold alloyed with Rhodium. 299 
and left the filtre besmeared with black, whieh on drying, 
turned to bright olive-green. ‘The same, saturated with 
tric acid, left a sediment of a purplish or ace, red pil 
and with tincture of galls, one of a dark citron-gray ; a proo 
of its not being osmium. 
The black powder being separated from the gold by mer+ 
cury, was dissolved in muriatic acid, and the solution, by 
boiling, assumed a_ beautiful orange-red-color. he green 
could not be reduced by the Chevalier Mendez with the blow- 
pipe, but he observed that some points detonated like nitre, 
which is a property of rhodium 
This greea powder, which I wished to treat separately, 
being passed with water from a capsule to the matrass, 
came again black; and on adding it to the red solution, 
which I had again "caused to boil, it appeared gray in the 
hot water, but resumed its red colour in cold. — Into this was 
put muriate of ammonia, which, by concentrating it, produ- 
ced an orange-coloured precipitate, which, after decantation 
and sufficient washing, was dissolved partly i in cold water, 
but mostly in hot, and, by a slow evaporation, me an in- 
finite number of orange-coloured crystals. all th being re- 
r se in the same crucible as ae the = 
duced per m oF bis p> 
= 
13.86 remain, aebick is the rhodium 5; 
and this being compared with 45.5, shows it to be 30.4 per 
cent. of allo 
I cannot matt to mention, that the potash produced quent 
cavities in the crucible, and that I extracted 130 grai 
protoxyd of eReee which were reduced in a clay aaraatite 
as far as practicable Lee 
Neither the Giasiatic acid, nor the aqua regia, dissolve 
the black powder ; the solution of potash dissolved some, and 
the remainder was treated with fat in a a crucible, and a 
white metallic points were immediately discovered. As they 
* | afterwards saw that tl aes bubbles were a the gold, as if it sought 
d to the rhediam: this 
to become separated from the placa - = to nite 
always maintained its white oioart ald oe plation influence it in this 
respect? I consider it as emivently prorense 
