Update on Atna’s Pinson Underground Project, Nevada
Bill Stanley, Vice President, Exploration for Atna Resources Ltd.
The Pinson Project is located in Nevada, one of the world’s premier gold mining regions with annual production of over 6.9 million ounces (2004). The vast majority of gold endowment and production occurs in Northern Nevada, along four major Sediment-hosted gold belts, (Carlin, Battle Mountain, Getchell, and Independence). Significant additional production comes from epithermal volcanic-hosted deposits of the Northern Nevada Rift and the Walker Lane Volcanic provinces. Current gold reserves are approximately 64 million ounces. Total production may eventually exceed 200 million ounces as new discoveries such as Cortez Hills (>10 million contained ounces gold) and Pinson continue to add to the resource base in this prolific gold region.
The Pinson Mine Project is situated within the 30 million ounce Getchell Gold Belt approximately 15 kilometers southwest of Newmont’s Twin Creek Mine complex (352,810 ounces of gold production in 2004 & 5.8 million ounces of gold in various categories) and 8 kilometers south of Placer Dome’s Getchell/Turquoise Ridge Mine Complex (162,637 oz. Au production & 16.9 million ounces of gold in all mineralized categories). The Pinson Project includes over 13,000 acres of private fee lands and federal lode mining claims. Gold mineralization at the project is associated with elevated levels of mercury, arsenic, and antimony and is considered to be a Carlin-type gold system. Past mining of oxidized ores from the Pinson property by Pinson Mining Company produced over 985,000 ounces of gold prior to the closure of the mine in late-1999.
Modern exploration began in the early-1970s at Pinson and led to rapid discoveries by John Livermore, Peter Galli and Don Duncan of the Cordex Syndicate. Five open pits ore bodies were outlined between 1970 and 1985, including the A, B, C, CX, and Mag deposits. Gold production came from decalcified, locally silicified and/or argillized, fine-grained, limy sedimentary rocks of the Ordovician age, Comus Formation - the preferred host unit for the major deposits in the district. Mineralization at Pinson is focused along and adjacent to the range bounding Getchell Fault zone, a major ore control at the Getchell Mine.
Between 1997 and 2003, Pinson Mining (Barrick/Homestake partnership) drilled over 200 diamond and rotary drill holes (>70,000 m) on the property exploring the extensions of mineralization exposed at the bottom of the mine’s several open pits. This work resulted in a number of encouraging high-grade gold intercepts in several target areas. Atna’s initial exploration efforts commenced in August, 2004 and concentrated on two of these targets with known mineralization, the CX Zone, which plunges beneath the CX, C, and B pits and the Range Front Zone, which is the southern extension of the Getchell Fault zone. The program included a re-analysis of the mine data base and over 9,000 meters of surface rotary and diamond core drilling. The result was an NI43-101 compliant mineral resource with a measured and indicated resource of 500,000 ounces gold with an additional 1.3 million ounces of gold in the inferred category. Atna initiated an underground program in May, 2005 to explore the Range Front, which is the larger and higher grade of the two main zones of mineralization. The objective of the underground work was to convert a portion of the Range Front resource to reserve category, to explore the Pinson anticline, and to provide a platform for further deep exploration drilling. To date, 800 meters of underground access-drifting and an additional 8,000 meters of underground and surface drilling have been completed.
The most significant development at the project during 2005 was the discovery of the Ogee Zone in the adit driving to the Range Front. Channel samples in the adit returned a weighted average of 23.7 grams/tonne across a true width of 10.5 meters. Follow-up drilling was performed from a decline established parallel to the Ogee Zone. The first hole cut 45 meters grading 33.3 grams/tonne gold. From current geologic understanding, the zone has a strike potential of over 150 meters and down-dip potential of more than 300 meters. The Ogee mineralization is hosted in a zone of complex faulting with associated collapse breccias serving as the principal host unit. Atna expanded the scope of its original work program to accelerate the exploration of Ogee in addition to continuing exploration and development drilling of the Range Front mineral resource.
Early in 2006 Atna completed its earn-in requirements on the Pinson project and is currently awaiting Pinson Mining Company’s decision on its election to participate, sell or back-in to the project. Should Atna remain operator of the project, it will complete a feasibility study during the second quarter of 2006 and expects to begin ore shipments during the third quarter of 2006. |
