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Buena Vista Mining Company, Limited (Locality 39)

References: Annual Report of the Minister of Mines, British Columbia, 1905, 1907,
1910, 1911, 1913, 1914, 1915, 1917, 1918, 1919, 1920, 1922, 1923, 1925, 1926, 1927,
1928, 1929, 1930, and 1931; Geol. Surv., Canada, Sum. Rept. 1919, pt. B;
Memoirs 32 and 132.

The holdings of the Buena Vista Mining Company, Limited, consist
of the Big Missouri group on Big Missouri ridge about 5 miles north of
the Premier mine. The claims cover Harris creek and Big Missouri ridge
on the west side of the creek. The claims are underlain by volcanic rocks
that are for the most part rudely stratified, fragmental types. They strike
north to north-northwest and lie in an anticline. On the summit of Big
Missouri ridge they dip west at 45 degrees. Eastward along Harris creek
the angle of dip is lower, and east of the creek they dip at gentle to mod-
erate angles northeastward. The volcanic rocks are intruded, as for
example on the E. Pluribus and on other claims farther south, by feldspar
porphyry similar to that at the Premier mine. Narrow lamprophyre dykes
are numerous.

Prior to 1927 mining work consisted of making open-cuts, driving
short adits, and of diamond drilling. The purpose of this work was to trace
mineral deposits known on the surface and in shallow workings. On Big
Missouri ridge, on the Rambler, Buena Vista, Province, J. P. Fraction,
Jain, Golden Crown, and Big Missouri claims, where the volcanic rocks
in the main strike about north and dip west, some beds have been miner-
alized and others have not. The mineralized beds outcrop as long bands
of rusty rock containing pyrite, chalcopyrite, galena, and sphalerite that
are more abundant in some places than in others. The rocks are traversed
by shattered zones and fractures and perhaps because the rocks are very
much alike the fracturing is not concentrated into one main fracture zone.

On the Buena Vista claim two short adits less than 100 feet apart
expose a mineralized and silicified zone up to 10 feet wide. It strikes
north and dips at a moderate to gentle angle westward. Assays over
widths of several feet gave values in gold up to 5 ounces a ton, in silver
up to 5 ounces a ton, in lead and zinc up to 10 per cent, and less than 1
per cent in copper.

South of the Buena Vista claim, on the Province claim and on the
northern part of the Jain claim which is south of the Province, more than
thirty open-cuts expose sulphides in an area 800 feet in diameter. This
mineralized area is 1,500 feet distant from that on the Buena Vista and is
not connected with it. The rocks are somewhat sheared locally, the planes
of shearing strike north-northwest and dip about 45 degrees west. In the
open-cuts the rocks are silicified, are ribboned with quartz stringers trend-
ing north to north-northwest, and hold pyrite, sphalerite, galena, and
chalcopyrite. In places bands of fairly heavy sulphide up to 3 feet wide
strike north to northwest, but in general the mineralization is more dis-
seminated with here and there quartz-sulphide veinlets. Locally sphal-
erite is rather plentiful. Open-cuts and a short adit near the southwest
corner of the Province claim and open-cuts for several hundred feet to the
east reveal massive pyrite, sphalerite, galena, and chalcopyrite. The min-
eral bodies on the Province appear to be irregular lenses striking north to