26 
MUSEUM BULLETIN NO. 30 . 
MINERAL DEPOSITS. 
The mineral deposits of East Sooke peninsula are of two 
types, copper and iron deposits. The former are of much greater 
economic importance. They are found in the large hornblendite 
zones which have suffered from a second period of faulting with 
consequent trituration of the hornblende crystals. The universal 
association of the ores with the hornblendites is apt to lead to 
die conclusion that the same solutions which carried the ores 
also hornblendized the rock, but the following facts show clearly 
that the true sequence of formation was: (1) hornblendite; 
(2) fault; (3) ore deposition. 
Fresh, slickensided surfaces are common in the large horn- 
blendite zones, whereas, all other textures are destroyed ; hence 
these surfaces were formed subsequent to hornblendization. 
Small, un faulted hornblendite zones are coarse and pegma- 
titic in texture, and the large ones are principally made up of 
fine-grained hornblende, which under the microscope is seen to be 
brecciated material. Hence, again, faulting followed hornblend- 
ization. 
Aplitic stringers cut the small, unfaulted, hornblendite zones, 
but none cut the large ones. Presumably such stringers once 
existed, but have been destroyed by faulting. 
Non-faulted hornblendite zones carry no chalcopyrite, hence 
deposition of copper did not accompany hornblendization. 
The sulphides in the ores are universally found in distinct 
cracks in the hornblendite, not intergrown with the hornblende; 
hence deposition is subsequent to and not contemporaneous with 
hornblendization. 
The sulphides are sometimes found deposited in cracks, the 
walls of which are slickensided, and sometimes ore veinlets cut 
across slickensides. Hence ore deposition was subsequent to 
faulting. 
As mentioned, the ores consist largely of chalcopyrite, dis- 
seminated more or less thickly in small cracks and veinlets 
throughout the hornblendite mass. The percentage of chalcopy- 
rite present may vary all the way from zero up to 100 per cent; 
occasionally ore chutes occur consisting of dense, massive chal- 
