MINERALS AND GEOLOGY OF CANADA. 181 
general by a dark scoria. One hundred parts contain: sulphur 20.2, 
copper 79.8. This valuable ore occurs in some abundance at the 
Bruce Mines, Lake Huron. It is also found at Prince’s Mine on 
Spar Island, Lake Superior, as well as in the Michipicoten Islands and 
in the Island of St. Ignace on that Lake, associated with copper 
pytites, native copper, &c. It occurs likewise (with purple copper 
pyrites, &c.,) im the eastern metamorphic district : as in the townships 
of Leeds and Inverness in Megantic county. In the former of these 
townships it lies, according to Sir William Logan, in a ferruginous 
dolomite, associated with specular iron ore and a small quantity of 
native gold. 
Galena :—Lead-grey, with black and somewhat shining streak. In 
amorphous masses of lamellar or granular structure, and in monome- 
tric crystals—more especially in cubes and cubo-octahe- 
drons, fig 28. It breaks easily, owing to its well-mar- 
ked cubical cleavage, into rectangular fragments. H. 
2.5; sp. gr. 7.2-7.7. Decrepitates before the blow-pipe 
Fie 28. and yields lead globules, with the deposition of a yellow 
coating on the charcoal. One hundred parts contain: sulphur 
13.4, lead 86.6; but a portion of the sulphide of lead is generally 
replaced by sulphide of silver. The silver in most of the Canadian 
samples, however, is insufficient to meet the cost of its extraction. 
Galena is the source of nearly all the lead of commerce. It occurs in 
Canada in very many places, but nowhere, apparently, in large 
quantities. It is chiefly found in connection with the crystalline 
limestones of the Laurentian formation, associated with crystallized 
cale-spar and sulphate of baryta, and sometimes also with zinc 
blende and iron pyrites. It occurs thus, occasionally forming thin 
veins, in the townships of Lansdowne and Bastard, (Leeds County, 
C.W.;) Bedford (Frontenac County, C.W.;) Fitzroy (Carleton 
County, C.W.;) Ramsay (Lanark County, C.W. ;) Petite Nation 
(Ottawa County, C.E.;) and, in smaller quantities, in many other 
townships lying more especially along the southern outcrop of the 
Laurentian country. Galena has been met with also in the Huronian 
rocks of the Michipicoten and Spar Islands, Lake Superior, associated 
with copper ores, calc-spar, amethyst-quartz, &c., and on the neigh- 
bouring shores. Also in the metamorphic district of Eastern Canada ; 
more especially in the quartz veins of the Chaudiére Valley (with 
zinc blende, common and magnetic pyrites, native gold, &c.) as in the 
Seigniories of Vaudreuil and St. George. 
