Foresthill Exploration and Mining Corporation
These seventeen (17)
unpatented mining claims are located in the Canada Hill Mining
District, Placer County, California.
They cover approximately 820 acres and are contiguous. The original claims were filed in 1938, 1940 and 1945.
Reports were written in 1937, 1939, 1948, 1953, 1980, 1985
and most recently 1993-94 by geologists and engineers knowledgeable
and experienced with this region. The nearest town is 27 miles distant and the two lane Placer
County road which comes to within a half mile of the mining site was
paved by the county between 1983-1984 and is maintained by them.
On these claims are two tunnels. The Mexican tunnel was dug
sometime in the mid to late 1800's and is approximately ninety feet
in length and four feet high. It
was dug by hand, on bedrock and on an uphill angle and is located in
a blue colored tertiary gravel deposit (channel) approximately 30
million years old. The
Harris Tunnel (1952-56) is up hill of the Mexican Tunnel
approximately 250 feet and was drilled and blasted through hard rock
and into the same tertiary channel a distance of 150 feet where it
makes a turn and proceeds downward toward the Mexican Tunnel, they
are approximately 80 feet apart.
During the late 1980's and 1990's an overall evaluation of the property was undertaken which included mapping out-croppings and areas of significant quartz deposits, road systems, taking and analyzing aerial photographs, sampling and studying the geology of the property. An in-depth seismic evaluation of the property was planned and accomplished on approximately 25 acres. This Seismic evaluation has confirmed the existence of channels on the property and tied these channels from the Mexican tunnel through the Harris tunnel and north easterly approximately 1900 feet. The depths of these channels range from 30 feet to 50 feet below ground surface and the width of the channels on bed rock vary from 35 to 90 feet. We have a virtual picture and cross section projection of how these channels meander through this portion of the property. It is our intention to begin our work from the lower elevation at the Harris tunnel and follow the channels up hill.
As with other properties it
is difficult to determine reserves for placer gold mining operations.
We have discovered gold bearing bedrock which indicates we could
also have a lode deposit. We
have been designing a drilling program to verify the size of this
deposit. Approximately 25
of the 820 acres covered by these claims have been explored
using 4,835 linear feet of detailed refraction seismic survey
lines. The seismic
evaluation has disclosed the tertiary channel which is exposed at the
mouth of the Mexican tunnel and underground in the Harris tunnel.
The channel runs in a north easterly direction and our seismic
work has verified approximately 1900 feet.
There still remain approximately 795 acres that require
exploration, this will be an ongoing task.
An exploratory trenching program was started and bedrock was
reached and approximately 20 linear
feet was exposed. Gold
nuggets were found laying on the top of and in crevices within the
bedrock. From this location
we will be starting a new adit (tunnel) to follow the channel upward
through the Harris property. In
blasting bedrock to reach the placer deposits, a lode bearing bedrock
was uncovered, which assayed at 0.21 ounces of gold per ton of
material. (Gold at
$750/ounce equals $157/ton). It
is commercially feasible to mine at mineralized values of less than
$10/ton. This means that in
addition to the placer deposit there appears to be a lode deposit on
this property. We must now
determine the extent of both
deposits and modify the mining plan to optimize recovery of both.
In the vicinity of the Mexican and Harris tunnels including the area of
our seismic work there is in excess of 2,900,000 cubic yards of gravel
to be mined. The value of gold in this area is difficult to estimate but this
property could exceed 580,000 ounces.
There is an existing exploration permit.
The trenching program allowed us to dig an extensive pit exposing
the bedrock walls as well as the channel floor.
The bedrock uncovered was of black slate, softer than the
surrounding andesite bedrock described by Phelps in his geologic report. The bedrock was impregnated with pyrite crystals which became
larger as the channel floor was approached, approximately one inch
The Canada Hill
channel, a branch of the Tertiary American River, is believed to have
flowed northeast and east across Sailor Canyon and then southeast to
join the southwest-flowing main Tertiary channel near French Meadows.
The channel is steep, narrow, and has not been too productive.
The gravels are usually angular and poorly washed.
Bedrock is slate and quartzitic schist of the Blue Canyon
Formation (Carboniferous) and schist of the Sailor Canyon Formation
(Lower Jurassic). The
gravels are capped by rhyolite and andesite.
There are some gold-quartz veins that contain abundant sulfides.
When the gravels become exposed to
the air the pyrite or marcasite oxidizes rapidly to limonite, and in
many freshly exposed banks the distinction between the upper red and the
lower blue parts is prominent. The
blue gravel is simply that in which the pyrite or the ferrous silicates
have not yet been decomposed to limonite. As already stated, the placer
gold of California is, as a rule, of a high degree of fineness.
If it is assumed that this fineness, in the main Tertiary
channels, is 920, this means, of course, that 92 percent by weight is
composed of pure gold. The
remaining 8 percent consists almost entirely of silver.
The gold is a bright yellow, coarse, flaky, and smooth.
The nuggets have been rounded.
This is a premium jewelry gold.
Panning has shown colors in the upper gravels.
A 4,835 lineal foot,
detailed refraction seismic survey has been completed on the subject
property. Data was
collected in the field and the data was reduced to workable drawings.
The seismic lines were located in the field based on topography,
exposed geology, previously printed information and related field
selection parameters. All seismic data was recorded and high explosives were used
as an energy source. Geophones
were spaced at 10 to 25 foot intervals dependent on desired target and
control included hand level differences at each geophone station tied to
a base elevation at the portal (opening) of the Harris Tunnel.
A total of 8 refraction seismic lines were completed. Geoseismic profiles have been generated for each of the seismic lines. These profiles show an approximate ground surface, low velocity and assumed bedrock profile. The thin near surface refractor horizon is typically 3 to 8 feet thick and ranges in velocity from 820 to 900 feet per second. Beneath this horizon is the layer of interest which typically ranges in velocity from 5200 to 5400 feet per second. Bedrock velocities calculated from all eight seismic lines range from 11,900 to 12,200 feet per second. It is the depressions, or lows, on this high velocity material surface which are interpreted to represent the ancient stream course. This interpretation is supported by exposed gravel/bedrock channel at the portal of the Mexican Tunnel and underground in the Harris Tunnel. An interpreted channel map has been generated. This channel map clearly suggests the typical braided stream pattern commonly found in the gold bearing Sierran Tertiary channel system.
exploration trenching bedrock was blasted away to allow the excavator to
go deeper into the earth. This bedrock was later tested and assayed at 0.21 ounces
of gold per ton of rock. This
bedrock was located under geophones 205-206, line 2 .
The picture below is a CAT-235 excavator beginning to
dig an exploratory trench approximately 100 feet from the Harris Tunnel.
This trench was dug to a depth of 45 feet.
Work was forced to stop because of heavy snow fall, the project was
completed to a depth of 55 feet the following year.
This picture is of the same
trench. It shows the black
colored bedrock which was drilled and blasted to allow the excavator
to dig a deeper trench. This
bedrock was assayed and showed traces of silver and approximately 0.21
ounces of gold per ton of rock. This
is approximately $157.00 per ton with gold selling for $750.00 per ounce.
The sample was taken approximately 10 feet below the feet of the
miner in this picture.
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Foresthill Exploration and Mining Corporation