A considerable variety of rocks crops out in this district, including north- and northwest trending belts of slate, schist, quartzite, and limestone on the west; quartz porphyry to the south; a gabbroic intrusion in the central portion; and greenstone to the east. Portions of the region are overlain by Tertiary andesite. Much of the central portion of the area is covered with glacial detritus. A number of patches of Tertiary gravels yielded gold in the early days.
There are a number of north and northwest-trending quartz veins and several wide complex systems of quartz veins. The individual veins usually are only a few feet thick. These contain free gold and often abundant pyrite. Ore shoots can be several hundred feet long and the sulfides can grade many ounces per ton.
During the tertiary age the topography of the area was very different which meant rivers flowed in channels that now can be found on mountains and hillsides. Like the modern rivers they were very rich in gold and the erosion of the old channels enriched the modern creeks. The Continental claims cover a remnant of channel that was preserved, along with its gold.
The depth of the channel is 20 to 90 feet and the bedrock consists of slate. The gravel is mostly quartz as it is pre-volcanic and is capped by andesite in some places. The richest gravel is found nearest the bedrock.
This channel is the same that is found at the Monte Cristo mine in Sierra County.
Given the number of gold-quartz deposits and the presence of mineralized quartz float found on these claims I think it is likely that undiscovered hardrock deposits also exist here. Because the early miners had difficulty identifying and processing sulfide rich ores, I also think it is very worthwhile to test the sulfides found on the claims as this district is known for its rich sulfides.
Claims with this amount of unworked tertiary channel are exceedingly rare. While working the channel won’t be a small project it could be very profitable one. There are multiple areas to find gold on the claims in the meantime and working the ravine and metal detecting could yield some great results.