Near the south boundary of San Bernardino County, and about 75 miles
directly east of Mount San Bernardino, a new mining district has been
organized within the past two years, and considerable development work
accomplished by the claim owners, who, as usual, are men of limited
means.
This district is 22 miles northeast of Cottonwood Springs, 16 miles
north of Eagle Mountain, and about 6 miles south from Virginia Dale. The
belt is about 1½ miles in width and 5 miles in length. The veins trend
north and south.
This new district, which has been named the Monte Negras, or Black
Mountain District, has attracted considerable attention by the discovery
in one of the claims of nuggets of gold and quartz of extreme richness.
At the time of this discovery some newspapers in this county published
the report that the mythical “Pegleg Smith” Mine had actually been
found, which only added to the excitement produced by the bringing into
San Bernardino of several hundred dollars worth of specimens.
I visited this new district in the month of May, 1892, and spent several
days in making an examination of the claims and adjacent country. The
Monte Negras camp is on the south side of the range of hills 45 miles
northeast of Walters Station, on the line of the Southern Pacific
Railroad, being reached by a fair desert road. By fair I mean a heavy,
but not rough or hilly road.
Walters Station is nearly 200 feet below the level of the sea. From that
point every foot of the way is up hill, till a divide near Cottonwood
Springs is reached, at an altitude of 3,157 feet, the distance being 27
miles; from there to the foot of the wash, which extends 2 or 3 miles
from the base of the mountains, down hill 19 miles, where the altitude
is 1,300 feet. The altitude of the camp is 1,520 feet. All the mines
lying back in the mountains are at higher, though varying, altitudes,
the greatest elevation being 3,500 feet, at the Ramona. The neighboring
peaks rise from 200 to 800 feet higher.
This district is distant about 35 miles from Cadiz, on the line of the
Atlantic and Pacific Railroad. I have never traveled the road, and know
nothing of it, although I am told it is a good desert road. Wood is not
obtainable at all in the vicinity of the mines, and water is scarce, but
has been obtained by sinking a well in a basin at Virginia Dale, a few
miles north of these mines. A shaft was sunk 140 feet in the wash 3
miles south of the most southerly Monte Negras mines, but no water was
obtained. Bedrock was not reached at the depth mentioned, but it is not
unlikely water may be secured by continuing this shaft downward.
I mention all these drawbacks to what I otherwise believe to be
promising property, because I think the difficulties may be offset by
the fact that the ore is high grade.
The Monte Negras uplift consists, as far as my observation extended,
entirely of eruptive rocks, diorite, quartz porphyry, and fine-grained
more or less porphyritic rocks, cut by later dikes of felsite and
dark-green or black diorite. Epidote occurs in great quantity throughout
the region, usually associated with micaceous iron ore, which is found
in the form of veins and bunches everywhere. The iron ores contain no
precious metals, and are of no economic importance.
The region, although entirely eruptive, and in part volcanic (large
fields of basalt occurring on the western slopes) is in the immediate
vicinity of a large hill called Pinto, or Painted Mountain, which is
made up of metamorphic strata, chloritic and hornblende rocks, quartzite
and mica schist predominating.
The mineral-bearing veins of the Monte Negras District are all of the
fissure type, and are mostly quite simple in form. The gangue is quartz,
carrying iron and copper sulphurets, and the secondary products of those
minerals, iron oxide and copper carbonate, with gold and silver. No lead
or zinc was observed. The economic value of the ore lies almost,
evidently, in its gold contents, the silver occurring so sparingly as to
amount to very little. The bullion obtained from these ores is worth
about $17 per ounce. The ore ranges in value from $20 to over $100 per
ton. Observations on the principal mines of this district, viz.: Great
Eastern, Venus, Columbus, Summit, Porcupine, Schiller, Hillerman, Annie
Rooney, Ethel, Republican, Ramona, McKinley Bill, and Revenue, have to
be omitted in order to condense the report.