Professor Haussmann on Metdllurgic Crystallography . 345 
stone has occasionally the same crystalline form as native sul- 
phuret of copper. 
b. Sulphur et of Lead.— Galena reproduced in melting fur- 
naces has been already mentioned. It is formed by sublimation 
during the fusion of native galena, and frequently occurs in the 
form of crystals. Artificial galena, formed in the founderies of 
the Upper Hartz, generally contains, besides sulphuret of lead, 
also sulphuret of antimony, which may be easily explained, as 
galena veins frequently contain also antimonial galena. The 
crystalline form is cubical, as in galena. But it is remarkable* 
that the secondary crystallisations, which occur most frequently 
in native galena, are not observed in artificial galena, where the 
primitive form occurs, which very rarely occurs in the native. 
c. Sulphuret of Antimony. — Besides that galena, which is oc- 
casionally antimoniferous, there is a combination of it formed by 
sublimation, consisting of sulphuret of lead, along with a larger 
quantity of sulphuret of antimony, which is produced in the 
furnaces of the silver founderies in the Upper Hartz. This 
mixture may be distinguished by its very bright colour, and 
by its tendency to a radiated structure. In the pores of a 
specimen of this substance, produced in the foundery of Lauten- 
thal, I once found very thin prismatic crystals of pure sulphuret 
of antimony, about half a thumb in length, and bearing an ob- 
vious resemblance to crystals of native sulphuret of antimony K 
This production admits of a simple explanation, from the fact 
that antimoniferous galena is very frequently associated with 
common galena, occurring in the metallic veins at Lautenthah 
4. Oxides. 
Oxidised zinc is found in crystals in many of the iron foun- 
deries in Germany ; but of this substance, which at first sight 
bears a close affinity to phosphate of lead, the true nature has 
been hitherto unknown : and it is a new discovery of my es- 
teemed colleague Stromeyer, that the crystals mentioned above 
are composed of oxide of zinc, coloured with a small quantity of 
oxide of iron. 
The form of these crystals, which is so minute as not to ex- 
ceed the size of three lines, is a hexangular prism, the terminal 
planes of which, as in sulphate of lead, are frequently incom- 
