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by decrease in metallic minerals. . . . But other contact metamorphic
deposits are large and have supplied ore for continuous mining operations
extending over many years. The irregular character and erratic dis-
tribution of these deposits, however, make it necessary to observe caution
in estimating ore reserves, and generally for blocking out ore the exposures
of such deposits must be closer and more nearly continuous than those of
sedimentary deposits or persistent veins. Iron oxide deposits of this class
likewise show great variation in size. Several bodies of magnetite in the
Philipsburg region, Montana, contained only a few thousand tons. On the
other hand, the magnetite bodies that replace limestone at Cornwall, Pa.,
are extensive. Perhaps the most extensive deposits of contact metam-
orphic iron ore in the United States are those of Iron Springs, Utah, and
the Eagle mountains, California.”

Tron deposits of different character from these occur here and there
near the west coast, but, with the exception of the limonite occurrences,
they are of very smal] extent and of no importance. The tabulated state-
ment given below shows the relative importance of the different geological
types and the principal deposits belonging to each.

| [GEOLOGICAL CLASSIFICATION OF THE IRON DEPOSITS
A. Contact Metamorphic Deposits

(1) Macnerire Deposirs. The principal mineral is magnetite, and
in most cases the mineralizing intrusive is of the diorite clan.

(a) Host is Limestone
Conqueror
Sirdar Bugaboo creek
Little Bobs-Baden Powell }
Other Bugaboo Creek and Gordon River deposits
Harris creek, Port Renfrew
Sarita river, Barkley sound
Sunshine, Barkley sound
Defiance, Alberni canal
Magnetic, Henderson lake
Violet, Eioageiat lake
Stormont, Glengarry Nest ie:
Rob Roy, Prince Charlie { Nootka sound
Lord of the Isles No. 4, Barkley sound
Kennedy lake, Clayoquot sound

(b) Host is Volcanic Tuff or Andesite
Darby and Joan, Alberni canal
Copper island, Barkley sound
Black Prince No. 3, Barkley sound
Agnes, Hesquiat lake
June, Quatsino sound (in part)
Ingersoll river, Quatsino sound
Crown Prince No. 5, Barkley sound
Bald Eagle No. 2, Barkley sound

(ce) Host Doubtful, Due to Intense Metamorphism
Tron Chief, Barkley sound
Beck’s claim, Clayoquot sound .

(2) Copprr-MacnetitE Deposits. Chaleopyrite and bornite are
associated with magnetite in deposits of this class, and in most
cases constitute the principal value.

Tidewater, Sydney inlet
Kokshittle arm, Kyuquot sound

June, Quatsino sound (in part)
Old Sport, Elk lake, Quatsino sound

(3) SpecuLaRITE Deposir
Sunshine, Barkley sound (in part)