37 
On Haidingerite , a new Mineral species . 
From this result it is evident, that Haidingerite is composed of 4 atoms of sul- 
phuret of antimony, and 3 atoms of proto-sulphuret ol iron $ for, in that suppo- 
sition, calculation gives : 
Sulphur 0 2985-18 at. or sulphuret of antimony 0. 732-4 at. 
Antimony... 0*5330- 4 at. proto-sulphuret of iron 0. 268-3 at. 
Iron 0 1685- 3 at. 
1*000 
1*0000 
Its formula then, is 3/s 2 -f 4 sb s 3 . This formula, complicated in appearance, 
expresses, however, a verv simple relation ; for it shows that Haidingerite is so 
constituted, that in the negative sulphuret, (sulphuret of antimony,) there is twice 
as much sulphur as in the positive sulphuret, v 8U ^P ,luret ot iron 0 t ^ le same ratio 
has been already found in jamesonite, analysed by Mr. H. Rose, and which is 
composed of 4 atoms of sulphuret okantimony, combined with 3 atoms ot sulphuret 
of lead. 
The existence of Haidingerite as a peculiar species, seems incontestible ; for, in 
the first place, the sulphurets of which it is composed, are found in atomic pro- 
portions and in a simple ratio ; in the second place, one of these, the sulphuret of 
antimony, is found indeed in the isolated state in nature, but the other sulphu- 
ret, the proto-sulphuret of iron, does not exist in that state, since magnetic pyrites, 
which is the least sulphurized of all the native sulphurets of iron, is a combination 
of proto-sulphuTet and of per-sulphuret. In fine, as the proto-sulphuret of iron is 
verv strongly magnetic, if it was only mixed with the sulphuret of antimony in 
the Chazeile mineral, it would certa nly communicate to that mineral the pro- 
perty of moving the magnetic needle: now, I have already remarked, that Haid- 
ingerite does not possess that property : therefore, there is a combination between 
the two sulphurets. 
Haidingerite is very easily imitated by synthesis. The two sulphurets of anti* 
mony and iron will combine in all proportions, at the temperature of their fusion ; 
and it is probable that they will be discovered also in nature, united in other pro- 
portions than in the mineral of Chazeile. 
In the manufactories of France, for preparing regulus of antimony, the practice 
is to roast the sulphuret in a reverberatory furnace, and to melt the roasted mat- 
ter afterwards in crucibles, with carbonate of potash and charcoal. It is evident that 
by applying this process, as it has been done, to Haidingerite, pure antimony can- 
not be extracted from it ; for the roasted material is a mixture of oxyde of antimo- 
ny and oxyde of iron. Now, these two oxydes being reducible almost equally easy, 
and the two metals having a great tendency to combine together, there must be 
produced with the reducing fluxes, antimonmret of iron. This is actually the 
case, and I have ascertained, by experiments on a small scale, that the smallest 
trace of iron does not remain in the scoriae, when the ore has been, completely de- 
sulphurized by roasting 
It will be easy, however, to extract good regulus from the Chazeile ore, and 
being abundant, it is desirable not longer to delay working it. I published in the 
Ann. de Chxm. el tie Physique , xxv. 379, several methods that might be employed. 
The easiest to practise, would be to melt the ore in crucibles, or reverberatory 
furnaces, with the addition of iron and a little sulphate of soda, mixed with char- 
coal. By adding only the proportion of iron strictly necessary, the antimony 
alone will be desulphurized, and the sulphuret of iron found in the ore, as well as 
that which would result from the reaction of the metallic iron on the sulphuret of 
antimony, would remain entirely in the scoria, rendered very fluid by the pre- 
sence of sulphuret of sodium. 
The exact proportion of iron to be employed, would be 6 atoms, for 1 atom of 
the pure ore, or 337 per cent ; but it would be advisable to keep always below that 
proportion, at the risk of losing a little sulphuret of antimony in the scorias, be- 
cause that, if there was an excess of iron, a certain proportion of it would combine 
with the antimony, which would greatly alter its quality. 
