124 
[Assembly 
Having spoken of the general formation of this district, we pro- 
ceed under our third head to speak of the more local deposites, 
such as copper, lead and iron. 
1. Copper, We shall not at present venture to say that the 
northern counties will be productive in this metal, though some 
iacts favor the opinion that it will. An ore of copper has been 
discovered at several places during the last season; it is the pyri- 
tons copper, or the sulphuret of copper and iron. One locality of 
this substance is on the Mascolunge lake, in the town of Alexan- 
dria; and two others in Gouverneur, St. Lawrence county. It oc- 
curs at several other places, which we were not permitted to ex- 
amine. 
The localities have not been explored to any great extent. On 
the Mascolunge lake the quantity of pyrites at the surface was 
very small. On breaking away the surface of the rock by blast- 
ing, it increased rapidly. The exploration of the ores of copper 
is nearly new in this country, hence it is impossible to entertain 
very just notions of the value of these mines; but as copper is a 
valuable metal, and its ores not very expensive to reduce, it is 
matter of some moment to explore and work the mines already 
known. 
This variety of copper ore yields about 30 per cent of copper. 
The composition of the Cornwall ore, yields, according to Phil- 
lips, copper 30, iron 32, sulphur 35. Copper pyrites resembles so 
much iron pyrites, which is of no value, that it may be easily mis- 
taken for that substance. It may be distinguished by a peculiar 
rich yellow colour, and its yielding to the knife. While iron py- 
rites is sufficiently hard to give sparks with steel. It is common 
also for the copper pyrites to be intermixed with the blue and green 
carbonates. 
Lead, Sulphuret of Lead, Much excitement has existed the 
last two years, and in fact still exists, in relation to this substance. 
The existence of lead in the northern counties has been known for 
many years. The Indians have supplied their wants of this arti- 
cle from some concealed places, ever since the country was set- 
tled. But little attention was given to this fact, and few or no ef- 
forts were made for its discovery, until a year since, when the 
successful opening of the great mine at Rossie excited a general 
feeling for discovery, and a willingness to hazard something in 
