Tonopah Gold Project

The Tonopah project is located on the prolific Walker Land Trend of Western Nevada on the northeast side of the San Antonio Mountains, located approximately 20 miles northeast of the town of Tonopah in Nye County. 

  

The Project consists of 444 unpatented lode claims covering an area of 4,054 acres. All unpatented claims are 100% controlled by Viva Gold Corporation (Viva). A 2% Net Smelter Return Royalty (NSR) with a 1% NSR buyout option exists on 185 of the unpatented lode mining claims that cover the core of the known mineralization. 

Cross section slice showing Opa upper surface (blue) and Tv Upper Surface (green) (Az 242).

Geology and Mineralization

The Tonopah property contains a near-surface low-sulfidation epithermal gold system which includes near vertical quartz-adularia-gold veins hosted by the Palmetto Formation argillite and the overlying Tertiary rhyolitic volcanics within a low-angle zone of mineralization which includes and often parallels an erosion surface discontinuity at the top of the Palmetto. Mineralization has been identified in a series of north-striking extensional structural zones within an overall mineralized trend along the north-northwest Walker Lane trend, covering an area over 2,000 meters long and 300 meters wide. 


  

The image to the right is a cross section slice showing upper argillite surface (blue) and upper tertiary surface (green) (Az 242) Scale in feet. 

Metallurgy

Results available to date indicate that gold and silver mineralization from the Tonopah project are amenable to recovery by cyanide leaching. Test work has been completed on both fully oxidized and sulfide samples, with little difference noted in recoveries.  Bottle roll tests on samples crushed at -200 mesh show gold recoveries of as high as 93%. A particle size versus gold recovery relationship has been demonstrated.  It is noted in some of the test work that coarse gold present in samples maybe contributing to delayed recovery in cyanide solution.


Gravity pre-concentration was recommended in some of the early studies to segregate coarse gold from the material prior to cyanide leaching. Gravity testing indicates that gravity methods might be useful for pre-concentration, particularly in higher grade materials.


Flotation test work completed on high grade gold samples, indicates that a high percentage of gold can be recovered to concentrate by froth flotation. However, the test work appears to indicate that gravity/cyanidation showed better performance than flotation/cyanidation.


Additional testwork on a range of samples reflecting differing rock types and grade ranges is required to determine potential process routes and recoveries. 

Mineral Resources are presented at a 0.250 g/t (ppm) cutoff grade, and inside a $1250 pit shell using a 42 degree average pit slope, which constitutes ‘reasonable prospects for economic extraction’. 

 Plan view of the $1,250 pit shell. 

Project Infrastructure

The Tonopah Project is currently an exploration/evaluation stage project. The site has excellent logistics and access for exploration, being a short drive from the town of Tonopah, Nevada, with good road access, communications, and access to contractors and labor. Las Vegas, a city of 2 million people with significant construction and manufacturing infrastructure, is located 210 miles southeast of the project via US Highway 95. There are major Komatsu and Caterpillar dealers and supply depots located in Las Vegas, as well as Cat and Komatsu parts depots and mining-specific machine shops in Round Mountain, approximately 30 miles north of the project. Power and water is available, although water rights will need to be acquired. 

Environmental and Permitting

Viva has the permits and authorizations necessary to conduct mineral exploration activities on both public and private land. Authorizations assumed include:


  • Decision Record (DR) and Findings of No Significant Impact (FONSI) issued by the United States 
  • Department of the Interior Bureau of Land Management (BLM) Casefile NVN-076629, and
  • Reclamation Permit 0210 issued by the Nevada Division of Environmental Protection (NDEP) Bureau of Mining Regulation and Reclamation (BMRR).

The operator previous to Viva, Midway Gold, undertook several studies to support potential future surface and/or underground mining operations. The studies identified and evaluated baseline hydrogeologic conditions, groundwater quality, storm water controls, mine dewatering requirements, ore and waste rock geochemistry, surplus dewatering water management options including re-infiltration and underground injection. 


Of note, studies conducted in 2010 predicted an average of 1,000 to 2,000 gallons per minute dewatering rate requirement for a potential underground mining operation. Geochemical testing of waste rock that would be encountered in potential underground decline development reported a low potential for acid rock drainage.

Work Plan

  • Complete a Preliminary Economic Assessment (PEA) to determine the economic potential of the project, and to consider possible trade-offs to processing and mining methods for the deposit.
  • Complete additional metallurgical test work with the objective of providing information for cost and recovery assumptions to be incorporated into the PEA. 
  • Long-lead baseline work should be considered for environmental and water quality monitoring to support further exploration and development efforts.
  • Approximately 4,000 meters of drilling in 25 -30 holes are recommended to address gaps in the solids models caused by low drill density in certain areas of the main mineralized trend. Samples from these holes would also provide additional fresh material for these metallurgical samples. 

The proposed work plan, including completion of the PEA, drilling, metallurgical test work and initial environmental field work, is expected to cost $950,000.