VANCOUVER, May 30, 2011 /PRNewswire/ --
- At a 0.5% Copper Cut-off Grade, Total Mineral Resources at the
Minto Mine now Exceeds 1 Billion Pounds of Copper
Capstone Mining Corp. ("Capstone") (TSX: CS) today announced the
result of a National Instrument 43-101 compliant mineral resource
estimate for the Wildfire/Copper Keel area at the Minto Mine in
Yukon, Canada. Wildfire/Copper
Keel is now recognized as a southeastwardly extension of the Area
2/118 deposit which is currently being pre-stripped in preparation
for mining. The combined Area 2/118/Copper Keel/Wildfire mineral
resources are now recognized as a single mineral deposit and will
be referred to as the Minto South Deposit ("MSD"). The Copper Keel
region of this larger deposit model is still open and exploration
drilling is currently in progress with two drills.
"The exploration success at Minto continues to be translated
into mineral resource additions that support the near term growth
strategy at our mining operations. Since 2006 the Minto Mine has
realized steady expansion through a program of discovery and
feasibility in a series of phases that have increased mine life and
throughput. Capstone plans to follow up this latest mineral
resource addition with a new Pre-Feasibility Study (Minto - Phase
VI PFS) that is expected to start in the third quarter of 2011,"
said Brad Mercer, Vice-President,
Exploration for Capstone.
Additional Mineral Resources by Class in the Wildfire/Copper
Keel Region of MSD at a 0.5% Cu Cut-off Grade ("COG")**
Classification Tonnes Copper Gold Silver Contained Contained Contained
Cu Gold Silver
(000's)* (%) (g/t) (g/t) (000's (000's (000's
lbs)* oz)* oz)*
Measured (M) 3,176 1.09 0.39 3.35 76,071 40.0 341.8
Indicated (I) 6,198 1.04 0.34 3.18 142,498 67.9 633.9
Total (M&I) 9,374 1.06 0.36 3.24 218,570 107.9 975.6
Additional Inferred 1,113 0.98 0.33 3.22 24,066 11.6 115.3
*Rounded to nearest thousand; totals may not sum exactly due to
rounding. **Exclusive of all previous resources estimated for Area
2/118 deposit
Mineral resources that are not mineral reserves do not have
demonstrated economic viability. Mineral resource estimates do not
account for mineability, selectivity, mining loss and dilution.
These mineral resource estimates include inferred mineral resources
that are normally considered too speculative geologically to have
economic considerations applied to them that would enable them to
be categorized as mineral reserves. There is also no certainty that
these inferred mineral resources will be converted to measured and
indicated categories through further drilling, or into mineral
reserves, once economic considerations are applied.
Minto South Deposit (MSD) - Mineral Resource Estimate
Geological modelling using new drill holes from 2010 and 2011
(partial) in the Wildfire/Copper Keel area indicate that Wildfire
and Copper Keel are a southeast extension of mineralization located
on the Area 2 side of the previous Area 2/118 resource model and
not separate deposits as initially thought. Approximately 134 new
drill holes were added to the existing database of 235 holes to
estimate a mineral resource for the entire MSD. These new data
indicate a continuity of mineralization between Copper Keel
mineralization and the deeper levels of Area 2. The new model
indicates that there was also continuity of mineralization between
Wildfire and the shallower levels of Area 2 before erosion removed
mineralization and created the false impressions of a gap between
the two deposits.
The 219 million pounds of copper gained in M&I resource
class and attributable to the Wildfire/Copper Keel area of the MSD
block model was determined by tabulating all mineralized blocks at
the stated cut-off grade that lie outside of the southeast
perimeter of the previous Area 2/118 block model.
The table below is a tabulation of all mineral resources by
class for the combined Minto South Deposit at a 0.5% Cu COG.
Total Mineral Resources by Class for the Minto South Deposit at
a 0.5% COG***
Classification Tonnes Copper Gold Silver Contained Contained Contained
Cu Gold Silver
(000's)* (%) (g/t) (g/t) (000's (000's (000's
lbs)* oz)* oz)*
Measured (M) 10,091 1.23 0.46 4.1 274,474 149.7 1,319.8
Indicated (I) 26,295 0.96 0.31 3.3 552,706 263.1 2,812.9
Total (M&I) 36,386 1.03 0.35 3.5 827,181 412.8 4,132.4
Additional
Inferred 7,429 0.82 0.23 2.8 134,296 55.0 666.3
*Rounded to nearest thousand; totals may not sum exactly due to
rounding. ***This tabulation includes mineral resources previous
outlined for the Area 2/118 deposit. For new mineral resources
added by the new interpolation please refer to the previous
table.
Total Undeveloped Resources for the Minto Mine
The following table details the total of all of the undeveloped
mineral resources on the property at a COG of 0.5% Cu. The table
includes Minto North, Minto East, Minto
South and Ridgetop as listed form north to south. Any
resources remaining in the Minto Main deposit are excluded because
mining of this pit has been completed. Existing ore stockpiles are
also excluded. At the end of this news release is also a table of
the undeveloped mineral resources for Minto at select copper COGs.
Estimated grade and tonnage stated at copper COGs below 0.5% copper
are for illustrative purposes only; to show the sensitivity of the
mineral resource to changing copper COGs. Some of the estimated
grade and tonnage at lower COGs may lie outside of any constraints
imposed for "reasonableness of mining" purposes with respect to
National Instrument 43-101.
Mineral resources at higher cut-off grades are for illustrative
purposes and do not necessarily imply a higher potential for
economic extraction. Only those mineral reserves determined by
previous feasibility studies are currently considered economically
viable. The property-wide mineral resource numbers reported herein
are inclusive of all previously defined mineral reserves that are
currently supported by previous pre-feasibility work. Please refer
to the Technical Report titled Minto Phase V Preliminary
Feasibility Study Technical Report dated December 15, 2010 filed on SEDAR for any further
discussion about mineral reserves at Minto. A new pre-feasibility
study (Phase VI) is anticipated to start in the third quarter of
2011 to apply economic considerations to the newly estimated
mineral resources in the Wildfire/Copper Keel extension of the
MSD.
Total Mineral Resources by Class for all Deposits Outside of the
Minto Main Pit at a 0.5% Cu COG****
Classification Tonnes Copper Gold Silver Contained Contained Contained
Cu Gold Silver
(000's)* (%) (g/t) (g/t) (000's (000's (000's
lbs)* oz)* oz)*
Measured (M) 13,465 1.33 0.53 4.3 395,209 228 1,881
Indicated (I) 30,828 0.98 0.33 3.4 664,794 325 3,334
Total (M&I) 44,293 1.09 0.39 3.7 1,060,002 553 5,215
Additional
Inferred 8,360 0.88 0.27 2.9 162,429 72 792
*Rounded to nearest thousand; totals may not sum exactly due to
rounding. ****Excludes any resources remaining in the Minto Main
Deposit, where mining as now ceased, as well as existing stockpiles
of ore originating in the Minto Main Deposit.
Mineral Resource Estimate Methodology
The mineral resource estimate for the Wildfire/Copper Keel
addition to the Minto South Deposit reported herein was prepared by
SRK Consulting of Vancouver. The
estimate was completed in Gemcom Software GEMS(c) using a three
dimensional block model (10 m by 10 m by 3 m (vertical) block
size). The mineralization was interpreted into nine distinct
domains, modelled as wireframes and used as hard boundaries to
constrain estimation. Geostatistical analysis was completed on the
1.5m composite assay data for each of the metals, and variograms
were defined for each domain of mineralization. The grades for
copper and gold were interpolated into the block model using
ordinary kriging method. Whereas the silver grades were
interpolated using the inverse distance squared method only.
Interpolated results are reported in measured, indicated and
inferred categories and are based on continuity of the
mineralization and sample density.
Minto South Deposit (MSD) -- Mineral Resources by Class at
Select Copper Cut-offs
Contained Contained Contained
Copper Gold Silver
Cut-Off Tonnes Copper Gold Silver (000's (000's (000's
Classif-
ication (Cu%) (000's)* (%) (g/t) (g/t) lbs)* oz)* oz)*
Measured
(M) >2.0 1,370 2.59 1.14 9.20 78,095 50 402
>1.5 2,884 2.14 0.89 7.38 135,922 82 680
>1.0 5,134 1.74 0.70 5.93 197,205 114 966
>0.5 10,091 1.23 0.47 4.12 274,474 150 1,320
>0.4 12,070 1.10 0.41 3.67 294,001 157 1,406
>0.3 15,019 0.96 0.35 3.15 316,578 165 1,502
>0.2 19,147 0.80 0.28 2.62 338,964 173 1,596
Indicated
(I) >2.0 1,311 2.61 0.93 9.62 75,354 39 397
>1.5 3,243 2.07 0.73 7.60 148,205 76 782
>1.0 8,137 1.55 0.55 5.61 277,998 143 1,462
>0.5 26,295 0.95 0.31 3.32 552,706 263 2,813
>0.4 36,046 0.82 0.26 2.83 648,579 299 3,284
>0.3 50,105 0.68 0.21 2.37 756,391 338 3,829
>0.2 68,147 0.57 0.17 1.97 854,355 370 4,333
Minto South Deposit (MSD) -- Mineral Resources by Class at
Select Copper Cut-offs - continued
Contained Contained Contained
Copper Gold Silver
Cut-Off Tonnes Copper Gold Silver (000's (000's (000's
Classif-
ication (Cu%) (000's)* (%) (g/t) (g/t) lbs)* oz)* oz)*
Sub-total
(M&I)** >2.0 2,681 2.60 1.03 9.41 153,449 89 799
>1.5 6,127 2.10 0.81 7.50 284,127 159 1,462
>1.0 13,272 1.62 0.61 5.74 475,204 258 2,428
>0.5 36,386 1.03 0.35 3.54 827,180 413 4,132
>0.4 48,116 0.89 0.30 3.04 942,581 457 4,691
>0.3 65,123 0.75 0.24 2.55 1,072,969 503 5,332
>0.2 87,294 0.62 0.19 2.11 1,193,318 543 5,929
Additional
Inferred >2.0 136 2.71 1.37 15.13 8,087 5 55
>1.5 482 1.96 0.79 9.36 20,847 11 134
>1.0 1,312 1.48 0.52 6.22 42,841 21 250
>0.5 7,429 0.82 0.23 2.82 134,296 55 667
>0.4 11,307 0.69 0.18 2.33 172,320 66 844
>0.3 17,300 0.57 0.14 1.88 218,193 78 1,046
>0.2 25,850 0.46 0.11 1.52 263,831 90 1,267
*Rounded to nearest thousand; totals may not sum exactly due to
rounding. **Exclusive of all previous resources estimated for Area
2/118 deposit
Quality Assurance
The technical information in this news release has been prepared
in accordance with Canadian regulatory requirements set out in
National Instrument 43-101 ("NI 43-101") and reviewed by
Brad Mercer, P. Geol., Vice
President, Exploration for Capstone, the person who oversees
exploration activities on the Minto Mine property.
The mineral resource estimate reported herein for the Area
2/118/Wildfire/Copper Keel deposit was estimated by Wayne Barnett, Pr.Sci.Nat. and Marek Nowak, P. Eng. of SRK Consulting. Dr.
Barnett is the Independent Qualified Person under NI 43-101
responsible for the MSD mineral resource estimate and has reviewed
the information in this release in respect of the MSD mineral
resource estimate. The database used to estimate the
Wildfire/Copper Keel deposit was audited by SRK. SRK is of the
opinion that the current drilling information is sufficiently
reliable to extend with confidence the boundaries of the
mineralized domains from Area 2 into Wildfire/Copper Keel, and that
the assaying data is sufficiently reliable to support estimating
mineral resources. The mineral resources presented herein have been
estimated in conformity with generally accepted CIM "Estimation of
Mineral Resource and Mineral Reserves Best Practices" guidelines
and are reported in accordance with Canadian Securities
Administrators' National Instrument 43-101. Mineral resources are
not mineral reserves and do not have demonstrated economic
viability. In the opinion of SRK, the block model resource estimate
and resource classification reported herein are a reasonable
representation of the mineral resources at Wildfire/Copper Keel
deposit at the current level of sampling.
With respect to the MSD mineral resource estimate, the
analytical method for the copper and silver analyses is aqua regia
digestion of the samples followed by atomic absorption
spectroscopy. Gold is analysed by fire assay fusion with atomic
absorption spectroscopy finish. Analyses are carried out by ALS
Chemex in North Vancouver. When
visible gold is noted in drill core samples or regular fire assay
values appear abnormally high, screen metallic assay method is used
to determine the total gold content and gold content of different
size fractions. This is considered industry best practice when
dealing with coarse gold mineralization where a nugget effect is
suspected. This determination is accepted as the most
representative value and is used in the assay database for resource
calculations. Blank and standard samples are used for quality
assurance and quality control. Where more than two check samples
assay outside expected ranges, the entire batch is re-assayed.
After the completion of planned drill programs at Minto, random
check assays will be carried out by Acme Analytical of Vancouver.
Cautionary Note Regarding Forward-Looking Information
This document may contain "forward-looking information" within
the meaning of Canadian securities legislation and "forward-looking
statements" within the meaning of the United States Private
Securities Litigation Reform Act of 1995 (collectively,
"forward-looking statements"). These forward-looking statements are
made as of the date of this document and Capstone Mining Corp. (the
"Company") does not intend, and does not assume any obligation, to
update these forward-looking statements, except as required under
applicable securities legislation.
Forward-looking statements relate to future events or future
performance and reflect Company management's expectations or
beliefs regarding future events and include, but are not limited
to, statements with respect to the estimation of mineral reserves
and resources, the realization of mineral reserve estimates, the
timing and amount of estimated future production, costs of
production, capital expenditures, success of mining operations,
environmental risks, unanticipated reclamation expenses, title
disputes or claims and limitations on insurance coverage. In
certain cases, forward-looking statements can be identified by the
use of words such as "plans", "expects" or "does not expect", "is
expected", "budget", "scheduled", "estimates", "forecasts",
"intends", "anticipates" or "does not anticipate", or "believes",
or variations of such words and phrases or statements that certain
actions, events or results "may", "could", "would", "might" or
"will be taken", "occur" or "be achieved" or the negative of these
terms or comparable terminology. By their very nature
forward-looking statements involve known and unknown risks,
uncertainties and other factors which may cause the actual results,
performance or achievements of the Company to be materially
different from any future results, performance or achievements
expressed or implied by the forward-looking statements. Such
factors include, among others, risks related to actual results of
current exploration activities; changes in project parameters as
plans continue to be refined; future prices of mineral resources;
possible variations in ore reserves, grade or recovery rates;
accidents, labour disputes and other risks of the mining industry;
delays in obtaining governmental approvals or financing or in the
completion of development or construction activities; as well as
those factors detailed from time to time in the Company's interim
and annual financial statements and management's discussion and
analysis of those statements, all of which are filed and available
for review on SEDAR at http://www.sedar.com. Although the Company
has attempted to identify important factors that could cause actual
actions, events or results to differ materially from those
described in forward-looking statements, there may be other factors
that cause actions, events or results not to be as anticipated,
estimated or intended. There can be no assurance that
forward-looking statements will prove to be accurate, as actual
results and future events could differ materially from those
anticipated in such statements.
Accordingly, readers should not place undue reliance on
forward-looking statements.
For further information:
Capstone Mining Corp.
Cindy Burnett, VP, Investor Relations
Telephone: +1-604-637-8157
Email: cburnett@capstonemining.com
Website: http://www.capstonemining.com