Comstock Mining begins drilling in Harris
Miners get ready
to operate a two boom jumbo drill in September in the portal at the bottom of
Comstock Mining’s Lucerne Pit.
VIRGINIA CITY –
Comstock Mining Inc. has completed the entire 800-foot underground exploration
drift and has begun exploration drilling.
exploration drift at the north end of the existing surface mining operation is
called the Harris Portal, and it runs parallel to the previously discovered
dike-like masses of quartz porphyry that have intruded into the main lode.
Comstock began mining
near Virginia City in 2011 in surface pits. It began constructing a portal in
“Our teams have now
completed the targeted 800-foot segment of the Lucerne exploration drift, plus
expanded the drift an additional 200 feet towards the historic Succor vein
system and also completed approximately 10,000 feet of diamond core drilling,”
said Comstock President and CEO Corrado De Gasperis. “We have also begun
receiving assay results and look forward to reporting on these drill results
over the next few weeks and throughout January and early February.”
from Lucerne’s open cut mining toward underground exploration and development
marks a significant turning point for the company, said De Gasperis. The
Lucerne Drift represents the first substantial underground development in the
Comstock District in over 30 years.
The tunnel, when
complete, is designed to conduct an underground exploration drilling program
directed at a series of geological targets in the Silver City Branch of the
Comstock Lode, including the PQ target, the Succor vein systems and the
historic Woodville Bonanza system. These initial targets represent the core of
a broader geological corridor where the company is currently drilling.
drilling in the area, including the Succor-Holman drilling from earlier this
year, had suggested that a zone lying generally adjacent to and below the
Lucerne Cut had the potential to yield high-grade gold and silver. The current
program has been geared toward defining that potential.
The Harris tunnel was
driven in a northwest direction within the most stable footwall rocks. As of
Dec. 30, the total length of drifting is approximately 1,150 feet, including
six drill bays and an approximately 200-foot long crosscut, out of Bay 2, into
the veined system.
As of Dec. 30,
approximately 10,000 feet of diamond core drilling has been completed from the
six drill bays. Drilling takes the form of ‘fans’ that comprise a group of
holes having the same azimuth but different dips (between -50 and plus 40
degrees from horizontal). Each drill bay has two or three fans of drill holes
extending into the primary target, and in some cases to the Succor mineralized
zone. The core locations and orientations were designed to expand areas of
known high-grade mineralization identified from past surface drilling programs.
The drilling to date
has been either HQ3 or NQ core, and high-polymer muds are routinely employed to
enhance core recovery, which to date, has been excellent, according to
Comstock. The planned core-portion of the program will conclude in late January
2016, with total estimated core drill footage of approximately 12,000 feet.
Comstock is planning an additional 10,000 feet of reverse circulation drilling
in early 2016, in portions of the PQ target area plus some surface drilling to
better scope the extents of the Succor structure.
Comstock remains on
schedule to complete the first phase of the portal, drift, drilling, and
evaluation of these results by early February. Assay results, geological
interpretations and context will be forthcoming throughout January.
“We are focused on
this transition to higher-grade targets as we conclude the production for
Lucerne in 2015, including the completed SR 342 realignment,” De Gasperis said.
“We ended the year with good gold and silver grades, the lowest costs in our
history, and exceptional final gold and silver yields, as our life of mine
recoveries for Lucerne gold yields rose to an estimated 84-85%, from a previous
81%. This positions the platform and the district well for our future growth
January 02, 2016