406 
Tin. 
state of oxygenation in the aurum musivum, though 
there can be no doubt that it is oxy dated to a certain de- 
gree. 
We may therefore consider this substance as a sulphu- 
retted oxyd of tin, in which the oxyd is saturated with 
as much sulphur as it can retain at a low red heat. 
Aurum musivum may be made as well, and much more 
economically, in a crucible as in glass vessels. To make 
10 or 12lb. of it requires about eight hours ; but for an 
ounce or two in small experiments about an hour will 
suffice. 
Aurum musivum, when well prepared, is without taste, 
and entirely insoluble in water. The acids have no effect 
on it. When muriatic acid is boiled with it, some sul- 
phuretted hydrogen is generally given out and a little tin 
dissolved, but this is owing to the admixture of a portion 
of sulphuret of tin, for if the residue is washed, no sub- 
sequent treatment with this acid produces any effect. It 
is in this resistance to the action of muriatic acid, that au- 
rum musivum is particularly distinguished from the sim- 
ple sulphuret and the more and less oxydated hydro- sub 
phurets of tin. 
When aurum musivum is digested with a solution of 
potash and heated, it quietly dissolves and forms a green 
liquid, from which acids separate a yellow powder, which 
is the super-oxydated hydro- sulphuret, and not regenerat- 
ed aurum musivum. 
If mosaic gold is heated strongly in a close vessel, (that 
is, to as full a red heat as a glass retort will bear) it is en- 
tirely altered in its nature, a large quantity of sulphureous 
acid gas is given out, some sulphur sublimes, and the 
residue, which is nearly five-sixths of the whole, is a black 
brilliant metallic-looking mass, which appears to be chief- 
ly sulphuret of tin. A strong heat tlierefore causes the 
