The Chert Cliff Property is located in the Gold Bar District about 64 km (40 miles) northwest of Eureka, Eureka County, Nevada. Gold Bar, including the Chert Cliff project area, occurs within the southern section of the productive Battle Mountain Trend of gold deposits.
Chert Cliff is 100% owned by Columbus Gold subject to underlying royalties.
The project is leased to Great American Minerals, which is owned by Golden Predator. Per the lease agreement, Columbus receives annual cash payments, and a net smelter returns royalty. The Chert Cliff claims form part of Scorpio Mining's Gable Project.
Geology of the claims area consists of dolomitic siltstones of the Mississippian Webb Formation overriding massive Devonian limestones in thrust fault contact. Disseminated gold occurs in hydrothermally altered Webb siltstones and jasperoid. Drilling in 2008 also encountered gold mineralization in the lower plate Denay Formation.
Gold was discovered at Chert Cliff in the mid 1960's during the initial wave of prospecting for carbonate-hosted gold deposits following recognition of the Carlin model in 1961. The most intensive work was carried out by Asarco in the 1980's and succeeded in outlining the Chert Cliff gold deposit, with an historical resource of 1.4 million tons grading 0.04 opt gold (56,000 ounces of gold)*. Anomalous to ore grade intercepts were also encountered in isolated drill holes north and east of the resource area but were never followed up.
In 2008, Platte River (now Scorpio Mining) drilled seven reverse circulation holes totaling 1,567 m (5,140 ft) at Chert Cliff. The holes ranged from 91 m to 433 m (300 ft to 1,420 ft) in depth. All of the holes were drilled outside of the Chert Cliff resource area defined by Asarco in the 1980's, which is entirely hosted in the Webb Formation. The drilling encountered additional mineralization in the Webb Formation, and also low-grade but significant mineralization in the Lower Plate Denay Formation, which is a host of mineralization at the nearby, multi-million ounce Cortez Hill's gold deposit being developed by Barrick Gold.
The gold mineralization encountered in holes C-4, C-7, and C-8 in the Denay Formation occurs in carbonaceous limestone stratigraphically lower and about 183 m (600 ft) north of the resource delineated by Asarco. The best holes drilled were C-4, which encountered 55 m (180 ft) [from 52 m to 107 m (170 ft to 350 ft)] of 0.013 opt gold, including 12 m (40 ft) of 0.025 opt gold, in the Denay Formation, and C-1 with 58 m (190 ft) of 0.020 opt gold, from surface, in the Webb Formation.
The confirmation of mineralization in the Denay Formation opens up many additional targets for future drilling.
*Caution: A qualified person has not done sufficient work to classify the historical estimates contained herein as current mineral resources. Columbus Gold is not treating the historical estimates as current mineral resources and the historical estimates should not be relied upon.
Andy Wallace is a Certified Professional Geologist (CPG) with the American Institute of Professional Geologists and is the Qualified Person under NI 43-101 who has reviewed and approved the technical content of this project description. Mr. Wallace is the President of Columbus Gold and the principal of Cordilleran Exploration Company ("Cordex"), which is conducting exploration and project generation activities for Columbus Gold on an exclusive basis.
