Prospectors
were early encouraged by their discoveries, but greatly hindered by
many obstacles; only in 1908 have some tangible results finally
appeared. Conditions at the close of 1908 were highly encouraging for a
continued increase of production.
In
Mountain Province, the Mancayan copper mines, in Lepanto, have remained
idle, owing to failure of American capital to secure satisfactory terms
for purchase.
At
Suyuc, near the Lepanto-Benguet line in Mountain Province, gold occurs
both free and with pyrite in narrow veins in diorite, and there is a
small annual production, chiefly by natives. The main production of
gold in the Philippines and the large increase noted in this province
was from Antamok district, near Baguio, in the central part of Benguet.
Here the Bua Mining Company and the Benguet Consolidated Mining Company
have each done considerable development in pyritic gold-quartz ores,
partially oxidized, found in veins in basal diorite and later
andesites. Each of these companies operated a 6-stamp Hendy mill with
cyanide plants, and made an important production in 1908. Below the
Bua mine, on the Antamok, is the Camote mine, which has yielded gold
from oxidized siliceous ore. Near Baguio, from underground and surface
workings in partially decomposed andesites, there is a considerable
yearly production of gold by Igorots. On Gold Creek development work
has been done on the Naptung and other quartz veins carrying free gold,
gold tellurides, and pyrite. Similar work was done on the Copper King
mine and the claims of the Headwaters Mining Company also near Baguio.
In
the Province of Ambos Camarines the production was from the Paracale
district on the east coast of Luzon, and in 1908 was all of placer
gold. There was a large increase, already noted, over the output of
1907. The chief producer was the Paracale Dredging Company, operating a
dredge of the New Zealand type on Paracale River near the town. In the
last six months of 1908 a little more than 50,000 cubic yards of gravel
were handled by the dredge, according to the company reports, from
which was recovered slightly over $1 in gold per cubic yard. The dredge
yields free gold caught in the tables, gold in black sand concentrates
stored or shipped to smelters, and gold in pebbles and broken vein
material which is reserved for future milling. The operations of the
first dredge have been so promising that another of the same type was
in course of construction, and an American dredge from Masbate was
transferred to Paracale at the close of 1908. In addition to dredging,
a considerable amount of placer gold is annually recovered by natives.
The quartz mines of the district in metamorphic and igneous rocks made
no production in 1908, but development work was done on the San
Mauricio and Tumbaga mines recently acquired by American interests.
In
Sorsogon Province the only producing district was at Aroroy in the
northern part of the island of Masbate, where free gold is found in the
upper parts of quartz veins in igneous rocks; below water level the
gold is mostly in pyrite.
There
have been repeated attempts to work the gravels of Guino-batan and
Lanang rivers by dredging; but the Lanang dredge was wrecked in 1908,
and the results on the Guinobatan have been discouraging and the
dredge has been transferred to the Paracale district. The production
of Aroroy district was less in 1908 than in
