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Collection: Directories and Documents
Mineral Land Classification of Nevada County, California (1990) (235 pages)
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Page: of 235
MRZ-2a‘'®) Lower Spanish Mine (lode gold, silver, copper, lead,
zinc): Exploration conducted by Cedar Resources, Inc. during the
past three years at the Spanish mine (Locality No. 68, Plate 3b),
which has involved geologic mapping, drilling, geochemical
analyses, and geophysical surveying, has demonstrated the
presence of significant gold-silver-copper-lead-zinc
mineralization within massive and disseminated sulfide deposits
hosted in phyllite of the pre-Late Devonian Shoo Fly Formation.
The northerly-trending, 100-foot wide main ore body can be traced
along the surface for at least 1,800 feet. Mineralization
extends to a depth in excess of 400 feet down dip at 60 degrees
to the west. The area classified MRZ-2a®) includes only the
segment of the mineralized zone along which exploration drilling
has blocked out indicated and measured precious and base metal
reserves. Significant mineralization is inferred to continue both
north and south into the area classified MRZ-2b‘"™,
MRZ-2a"-3) — Meadow Lake Mine (lode gold): Significant indicated
and measured gold reserves have been delineated at the Meadow
Lake (Excelsior) mine (Locality No. 328, Plate 3b) by exploration
drilling conducted in the mid-1980's by Callahan Mining. Gold
mineralization occurs locally along a series of north-northweststriking, cavity-filling quartz-tourmaline-pyrite veins hosted in
granodiorite in the vicinity of Meadow Lake. Parts of the vein
system presently are being mined by Kelmine Corp., Utah. The
abundance of tourmaline in the veins, the intense and pervasive
sericitic alteration of granodiorite over a wide area, the
presence of Mesozoic volcanic rocks in the immediate area, and
the occurrence of a vein-hosted molybdenum prospect (Locality No.
334, Plate 3b) located nearby suggest that the mineralization
could be associated with a sub-volcanic island-arc porphyry
system (Bowman, 1983).
Areas Classified MRz-2b™
MRZ-2b‘"%) — spenceville Mine (copper, lode gold, silver): This
area contains a massive sulfide deposit enriched in copper, gold,
and silver that is hosted in volcanic rocks of the Late Jurassic
age Smartville Complex. Copper was discovered at Spenceville in
the early 1860's (Locality No. 51, Plate 3a). From 1875 to 1887
about 150,000 tons of ore averaging five percent copper was mined
from this locality. Since the ore was recovered from relatively
shallow depths (maximum of 150 feet), additional copper and gold
resources are inferred to exist at depth and along strike.
MRZ-2b°"5) ~ tron Mountain/Robinson Ranch (copper, zinc):
Historic mining and geologic investigations, exploration
drilling, geochemical sampling, geophysical surveying conducted
in the late 1950's and early 1960's by Sharon Steel, in the mid1970's by Superior Oil Company, and again in part during the mid1980's by Nevcan Exploration, Inc., indicate that significant
Bal