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News Release - Wednesday, July 11, 2007
Atna Increases Resource at Pinson
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Vancouver, B.C.
(July 11, 2007). Atna Resources Ltd. (ATN:TSX) is
pleased to announce the completion of a revised estimate of mineral
resources on the Pinson Property, Humboldt
County, Nevada. The
revised
estimate includes drill holes that were completed and assay data
received after the January 2006 cut-off date for the last resource
estimate (Atna news release, April 6, 2006).
The revised estimate results in a significant increase in the total
gold resource and in the transfer of additional mineralization from the
inferred category to the measured and indicated categories. The
Measured + Indicated categories increased by 50% from 712,600 ounces to
1,063,000 ounces at an average grade of 0.42 ounces gold per
ton.
Inferred resources increased by 9% from 1,053,700 ounces
to 1,146,600
ounces with an average grade of 0.34 ounces gold per ton. The revised
estimate is shown in the following table.
Resources Summary (RF, CX, Ogee, CX-West)
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Tons* Grade (Au opt) Contained Au*
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Measured 1,152,400 0.454 523,200
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Indicated 1,353,500 0.399 540,600
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M + I 2,505,000 0.424 1,063,000
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Inferred 3,374,500 0.340 1,146,600
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(Cut-off grade equals 0.20opt Au)
* Columns do not add up due to rounding
The resources estimate was completed in accordance with conventional
industry practice using a the commercial software (Surpac
5.2) and its
inverse distance squared algorithm to calculate 10x10x10 foot blocks
within geologically interpreted 0.10 ounce per ton grade shells. The
resource classification of each block in the model is based on the
distances from drill intercepts as follows:
Measured blocks: within 50
feet of a drill intercept.
Indicated blocks: 50 to 100
feet from a drill intercept.
Inferred blocks: 100 to 300
feet from a drill intercept.
A full technical report in support of the estimate will be filed on
SEDAR within 30 days.
David Watkins, President and CEO of Atna stated,
"We are excited by the
possibility that the exploration and development program about to be
initiated by PMC [Pinson Mining Company, a wholly owned subsidiary of
Barrick Gold Corporation] will continue to increase
the size of the
deposit and may encounter completely new zones of mineralization". PMC
has less than twenty-one months remaining to complete spending their US
$30 million back-in expenditure.
This press release and the mineral resource calculation were prepared
under the supervision and review of William Stanley, V.P. Exploration
of Atna, a Licensed Geologist and Qualified Person
with the ability and
authority to verify the authenticity and validity of information
contained within this news release. The projections from drill hole
data points are consistent with projections made in the original
resource estimate for the property, which were prepared by Rob Sim, an
independent consulting resource geologist, first published in February
2005, supported by Technical Reports filed on SEDAR in March 2005, and
subsequently revised and re-filed in December 2005. All analytical
results in this news release are from samples prepared and assayed by
BSI Inspectorate Laboratories in Reno,
Nevada, an independent ISO
certified analytical laboratory. All gold analyzes were completed
using standard fire assay methods with appropriate replicate and
analytical standards to ensure high quality control and quality
assurance. ALS Chemex in Reno,
Nevada re-analyzed all
mineralized
intervals to verify assays reported by BSI Inspectorate.
For further information, please visit our website, www.atna.com, or
contact:
ATNA RESOURCES LTD.,
Kendra Johnston, Investor Relations Manager, Geologist
Tel: (604) 684-2285; E-mail: kjohnston@atna.com
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Copyright (c) 2007 ATNA RESOURCES LTD. (TSE:ATN) All rights reserved.
For more information visit our website at http://www.atna.com/ or send
mailto:info@atna.com
Message sent on Wed Jul 11, 2007 at 7:39:44 AM Pacific Time
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