44 
ECONOMICAL MINERALOGY. 
ORES OF LEAD, ZINC AND COPPER. 
Although these ores have been for a long time known to occur in various parts of this State, 
they have, for a few years past, in some counties at least, been objects of peculiar interest. 
It has, indeed, been supposed, that lead, zinc, and perhaps copper, would be ranked among 
our most important mineral productions. Whether these anticipations are well founded, will 
probably appear from the facts about to be presented. 
SULPHURET OF LEAD, or GALENA. Cleveland. 
Plomb sulfure. Hauy. '■— Hexahedral Galena, or Lead-glance. Jameson. — Hexaedrischer Bleiglanz. Mohs. — Galene. Beudant. 
Description. This mineral, which, here as in other parts of the world, is the common 
ore of lead, has a bluish grey colour, usually called lead-grey ; streak unaltered. The colour 
is liable to tarnish, and the mineral then becomes iridescent. 
It occurs massive and crystallized. When massive, it is granular or compact, and some¬ 
times striated or fibrous. When crystallized, it is foliated, and has a threefold cleavage 
parallel to the faces of the cube, which is the primary form. Sometimes the cube is trun¬ 
cated on its angles and edges, and sometimes it is elongated. It occurs also in octahedrons, 
cubo-octahedrons, &c. 
The following crystalline forms have been observed in this State : 
Rossie, St. Lawrence Co. 
Martinsburgh, Lewis Co. 
Rossie, St. Lawrence Co. 
Rossie, St. Lawrence Co. 
