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Dennis J. LaPoint
conjunction with the surrounding, more extensive low grade
zones. As an example of new gold mines being put into production,
a recent article in the Mining Record (June 7, 1995)
discussed a mine being developed in Nevada with an average
grade 0.0027 ounces per ton gold (900 ppb gold). The key is
enough tonnage of ore at a low stripping ratio for bulk mining
and extraction techniques.
COMPARISON WITH WESTERN SIERRA
FOOTHILLS AND KLAMATH MOUNTAINS,
CALIFORNIA
Dennis and Shervais (1995) cite the Klamath Mountains
and the western Sierra Foothills of California as analogs to
the tectonic setting for the northwestern Carolina Terrane.
The Klamath Mountains are a well documented magmatic
arc and accretionary wedge (Hacker and others, 1993). Both
of these terranes are well known for their historic gold production
(Clark, 1970; Hotz, 1971). Probably the best known
district is the Mother Lode, a 120 mile-long system of linked
en echelon gold-quartz veins and mineralized schist and
mafic volcanic rocks. Other districts whose geologic
descriptions are similar to West Springs include the Allegheny
district in southwest Sierra County which is the most
famous high grade gold district in California. The value of
gold produced from this district is estimated at over $50 million
with much of the production from small but spectacularly
rich ore bodies. Gold quartz veins occur in
amphibolites; the veins are characterized by their extreme
richness, erratic distribution, and small size of ore shoots.
The mafic volcanic rocks have been cut by many basic and
ultrabasic intrusions. At the Angels Camp in the Mother
Lode region, gold deposits occur in amphibolite and chlorite
schist as massive quartz veins, zones of parallel quartz
stringers, and bodies of mineralized schist and greenstone.
Calcite, talc, ankerite, and sericite are common gangue minerals
in the ore (Clark, 1970).
CONCLUSIONS
The major gold rush in the southeastern US predated the
California Gold Rush of 1849 (Feiss, 1993). Early prospectors
focused on mining coarse visible gold associated with
quartz veins and free gold found in saprolite after oxidation
of sulfides. As with other gold mines in the 1800’s, the technology
to recover gold from lower grade sulfidic ores did not
exist. Since the California gold rush, most mining and exploration
has been in the western part of the United States.
There you can see rocks to sample, and mineral rights can be
claimed by staking the land. There is no royalty on claims
and no need to deal with individual landowners.
Now, new technology and gold prices allow for the
recovery of gold from lower grade sulfidic ores, such as
those at the Ridgeway mine. However, the level of exploration
activity remains low in the southeast for a variety of reasons.
First, the geology is still poorly understood with much
of the area unmapped at the 1:24,000 scale. Secondly, the
deposits are poorly understood and described. Exploration
geologists from the western U.S. need to understand that the
same geologic processes that formed gold deposits in the
west occurred here. Finally, company management that are
used to staking claims generally do not understand the methods
for leasing land in the eastern U.S., and are wary of the
permitting requirements for gold mines in the east.
The West Springs area is similar to other gold deposits
in the east. When companies come into a new area and
examine the old prospects, they may drill a few holes or
complete some geochemistry and geophysics, then decide
exploration is not warranted. The level of such activities is
too little to adequately test the gold potential of the deposit.
As can be documented at the Ridgeway and Haile gold
mines, the key to exploration success is persistence and drilling
in a systematic pattern. The gold deposits of the West
Springs area may or may not be mined at some future date,
but prospecting and drilling to date remain incomplete.
Metal deposits are excellent indicators of tectonic environments
(Sawkins, 1990) and when mapping, geologists
should pay attention to unusual rock types that may represent
alteration, structure or exhalative units. Examples include
iron formation, sericitic schists, aluminosilicates, garnetiferous
beds, sulfidic units, etc. The type of metal deposits may
provide further clues to understanding the tectonic setting of
the rocks and providing key stratigraphic markers.
A number of core holes have been drilled in the southeast
by mining companies, most of them in barren rock.
When the project is completed, the companies need to dispose
of the core. The South Carolina Geologic Survey has
attempted to save and store as much core as there is room to
store. Core is often the best example to fresh rock available
for research and mapping in the southeast, but too little has
been utilized by geologists in their research. Core is a valuable
resource that can be used by all geologists, and state
surveys should be encouraged to serve as depositories for
core offered to them. Companies should be encouraged to
donate core and associated data.
REFERENCES
Anonymous, 1995, Kinross Gold acquires 50% of Goldbanks
Nevada Property; The Mining Record, June 7, 1995, p. 21.
Becker, G.F., 1895, Reconnaissance of the gold fields of the southern
Appalachians: U.S. Geological Survey 16 th Annual Report,
v. 4, pt. 3, p. 251-319.
Butler, J.R., 1966, Geology and mineral resources of York County,
South Carolina: South Carolina Geological Survey Bulletin No.
33, 65 p.
Clark, W.B., 1970, Gold Districts of California; California Division
of Mines and Geology, Bull. 193, 186 p.
Dennis, A.J., 1989, Tectonogenesis of accreted terrane; The Caro-
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