Jan 19 2011
Comstock Mining Inc. (OTC Bulletin Board: LODE) announced today the results of the successful first phase of its drilling program.
The drilling program, as announced in a November 8, 2010 press release, was designed to advance the Company's strategic plan towards commencing commercial mining and processing operations and increasing the Company's validated gold and silver resources. The overall drilling program has a planned duration of about seven months, including development drilling in the Lucerne and Dayton Resource Areas, exploration drilling on high priority targets including targets in Dayton, Spring Valley and the East-side, and condemnation drilling in areas designated for possible heap leach pad expansion. The primary objective of the Fall 2010 drilling was completion of development and condemnation drilling supporting the Lucerne starter mine planning and the planned expansion of heap leaching capacity in American Flat.
The drill program began October 25, 2010, and completed 108 reverse circulation (RC) drill holes, totaling 26,490 feet, through the end of 2010. Drilling began with a single track-mounted RC drilling rig, and accelerated with the addition of a truck-mounted RC drilling rig and a second track-mounted rig. All three rigs are scheduled to continue drilling through the end of the program.
Development Drill Results for Lucerne Resource Area Starter Mine Plan
The first holes were drilled in the Lucerne Resource Area, focusing on the Hartford patented mining claim. Previous drilling identified this area as a possible, primary starter pit location. The Hartford infill drilling was designed to provide sufficient information for a detailed mine design, with 98 RC holes completed in 2010, totaling 19,865 feet. The holes were located within a mineralized area that measures approximately 825 feet by 500 feet. Chief Geologist Larry Martin commented, "The Hartford infill drilling represents one of our most productive drilling programs in terms of efficiency of drilling. The exceptional productivity was a result of a well-coordinated team effort, with drill planning and activities led by Project Geologist Steve Russell and supported by a drill rig and crew from DeLong Construction."
2010 Hartford Infill Drilling
The drilling results confirmed the importance of the quartz porphyry that provides a host for mineralization with enhanced grades. Intervals of significant mineralization (gold grades greater than 0.010 ounces per ton (opt) and length of at least 10 feet) were encountered in 85 of the 98 holes. Thirteen of the holes had significant mineralized intervals of at least 50 feet.
Typical Hartford Cross Section
"The information from the Hartford infill drilling program confirms the extent of the mineralized zone we expected and provides the information needed to finalize a detailed mine plan for a possible starter pit located entirely on private land," stated Michael Norred, Comstock Mining's Director of Strategic Resource Planning.
Development Drill Results For Heap Leach Expansion and Water Availability
Three RC holes, totaling 2,695 feet, were drilled to the north and west of the Company's existing heap leach facility in American Flat. The holes had two purposes: first, to test for near-surface mineralization in areas designated for possible heap leach expansion; and second, to assess water availability to meet the needs of an expanded heap leach operation. The holes were successful on both counts. No significant mineralization was encountered, and all three holes encountered water inflows during drilling operations.
Mr. Corrado De Gasperis, Comstock Mining Chief Executive Officer, stated, "The development drilling in the Lucerne Area and American Flat represented critical prerequisites for commencing commercial mining and processing. Our team completed an efficient execution of these immediate objectives."
Development and Exploration Drilling for the Dayton Resource Area
The Dayton Resource Area was acquired by the Company through two transactions in July, 2010. The results from 252 previously-drilled holes were used to model a mineral resource that was validated by the August, 2010 technical report authored by Behre Dolbear. Substantially all of that resource was within 230 feet of the surface, due to the shallow depths of the previous drilling. The new development drilling program for the Dayton Resource Area is designed in two phases. The first phase includes three east-west drill fences (rows of holes), with maximum depths of 1,200 feet, which will test the continuity of the mineralization to these greater depths, and will also validate the exploration model in the Dayton area."
The first phase of Dayton drilling began with one hole completed before the end of 2010. Results from this first RC hole, D10-01, on the first exploration fence, showed immediate and significantly better than expected results. The 825-foot vertical hole encountered 590 feet of significant mineralization with four intervals, totaling 305 feet, with elevated gold grades, and three deeper intervals, totaling 285 feet, with elevated silver grades.
"Our detailed review of the previous Dayton drilling indicated an extension of the successful geologic model developed in the Lucerne Resource Area," stated Larry Martin, Comstock Mining Chief Geologist. "This first hole not only corroborated, at more significant depths, our conceptual model but also discovered multiple, previously unknown anomalous silver zones that will be further explored."
Drilling Continues into 2011
Comstock Mining's drilling program is continuing into 2011 with the focus on the Dayton Resource Area. After completing the drill fences from the first phase, Comstock Mining's geologic team will design the second phase, adding infill holes for detailed mine planning. As mine planning for the Lucerne and Dayton Resource Areas continues, condemnation holes will be drilled to evaluate locations for both potential waste storage and for expanded or alternate processing locations. Exploration drilling will follow in other priority areas, including the East-side target and the Spring Valley target.
Mr. De Gasperis stated, "We were pleasantly surprised by the depth of the previously unknown mineralization coming from the Dayton Resource Area's initial drill results. In addition to supporting the future development of a second mine plan, our initial drill hole provides strong evidence for a meaningful expansion of the known, existing near surface resource. We are very much looking forward to continued, focused drilling in this area."