VANCOUVER, Sept. 4, 2012 /CNW/ - Great Basin Gold Ltd. ("Great
Basin Gold" or the "Company"), (JSE: GBG) announces updated mineral
resource and reserve estimates for the Company's Hollister Gold
Project ("Hollister") on the Carlin Trend in Nevada, USA as at June
30, 2012. The updated mineral resources and reserves reflect
depletion in excess of 370,000 tons which yielded approximately
400,000 gold equivalent ounces ("Au eqv oz") since commencement of
trial mining in 2008. The underground drilling program over the
past 18 months has been focused on increasing confidence in the
estimates of mineral resources and reserves to allow for improved
mine planning and forecasting. In addition, the underground
drilling focused on delineating material from the Tertiary
volcanic-hosted disseminated gold mineralization and the basement
meta-sediment hosted gold-silver low sulfidation epithermal veins.
Future drilling will seek to increase the mineral resource and
reserves to extend the life of the project. Mineral Resources The
mineral resource estimate for Hollister reflects important
additional information established from on-going underground
drilling and trial mining since the last resource estimate in
September 2010. The resource estimate, which is based on an in-situ
epithermal vein wireframe model and a Tertiary-hosted
mineralization wireframe and grade shell model, is now informed by
12,312 grade intersections, from a combination of 630 surface, 941
underground stope delineation and infill/cover boreholes, and 5,547
ore control channel samples taken during trial mining. The drilling
program provided infill data to further delineate stopes for trial
mining, which significantly improved the understanding of the
lateral and vertical geological continuity of the vein systems.
Trial mining has generated geological mapping and channel sampling
data that is being used for empirical reconciliation of the
resource wireframe model versus actual excavated vein. As a result,
more stringent parameters can now be applied to Measured and
Indicated classifications. The current estimates are based on
drilling, channel sampling and depletion of material mined to June
30, 2012. The informing data obtained from the underground drilling
campaign and trial mining to date has increased the confidence in
the resource estimate and also resulted in a decrease in the
estimated minable vein width. The combination of more rigorous
geological and vein modeling with narrower vein widths (averaging
1.6 feet), resulting in reductions in the estimated epithermal vein
resources included in the model. Silver ("Ag") grades included in
the resource update have also declined as a result of the inclusion
of the Tertiary volcanic hosted disseminated material where trial
mining has indicated a lower Au/Ag ratio.
___________________________________________________________________________
| | | | | | | | | | |Au Eq| | |Cut-off|Tonnes |Tons | Au | Au |Au
oz| Ag |Ag |Ag Oz| Oz | |CLASSIFICATION| oz/t | (000) |(000)|oz/t |
g/t |(000)|oz/t|g/t|(000)|(000)|
|______________|_______|_______|_____|_____|_____|_____|____|___|_____|_____|
|Veins | | | |0.922|31.60| 173| |197| 1| | |Measured | 0.10| 170|
187| | | | 5.8| | 079| 196| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.15| | |1.054|36.11| 170| |221| 1| | | | | 146| 161| | | | 6.5| |
039| 192| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.20| | |1.192|40.85| 166| |248| 1| | | | | 126| 139| | | | 7.2| |
006| 187|
|______________|_______|_______|_____|_____|_____|_____|____|___|_____|_____|
|Veins | | | |0.404|13.86| 325| | | 1| | |Indicated | 0.10| 729|
804| | | | 1.9| 63| 488| 357| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.15| | |0.506|17.33| 299| | | 1| | | | | 536| 591| | | | 2.2| 76|
309| 327| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.20| | |0.593|20.34| 277| | | 1| | | | | 424| 467| | | | 2.5| 86|
175| 302|
|______________|_______|_______|_____|_____|_____|_____|____|___|_____|_____|
|Tertiary | | | |0.939|32.20| 252| | | | | |Indicated | 0.10| 244|
269| | | | 2.0| 69| 539| 264| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.15| | |1.637|56.13| 238| |122| | | | | | 132| 145| | | | 3.6| |
516| 249| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.20| | |2.405|82.47| 229| |179| | | | | | 86| 95| | | | 5.2| |
497| 240|
|______________|_______|_______|_____|_____|_____|_____|____|___|_____|_____|
|Total | | |1 073|0.538|18.46| 577| | 65| 2| | |Indicated | 0.10|
973| | | | | 1.9| | 027| 621| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.15| | |0.729|24.99| 536| | | 1| | | | | 667| 736| | | | 2.5| 85|
825| 575| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.20| | |0.900|30.87| 506| |102| 1| | | | | 510| 562| | | | 3.0| |
672| 542|
|______________|_______|_______|_____|_____|_____|_____|____|___|_____|_____|
|Total M & I | | 1|1 260|0.595|20.41| 750| | 85| 3| |
|RESOURCES | 0.10| 143| | | | | 2.5| | 106| 817| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.15| | |0.787|26.99| 706| |110| 2| | | | | 813| 897| | | | 3.2| |
864| 767| |
|_______|_______|_____|_____|_____|_____|____|___|_____|_____| | |
0.20| | |0.958|32.85| 672| |131| 2| | | | | 636| 701| | | | 3.8| |
678| 729|
|______________|_______|_______|_____|_____|_____|_____|____|___|_____|_____|
___________________________________________________________________________
| | | | | | | | | | |Au Eq | | |Cut-off|Tonnes|Tons | Au | Au |Au
Oz| Ag |Ag |Ag Oz| Oz | |CLASSIFICATION| oz/t |(000) |(000)|oz/t |
g/t |(000)|oz/t|g/t|(000)|(000) |
|______________|_______|______|_____|_____|_____|_____|____|___|_____|______|
|Veins | 0.10| | |0.254| | | | | | | |Inferred | | 508| 560| |
8.72| 142| 1.1| 36| 590| 155| |
|_______|______|_____|_____|_____|_____|____|___|_____|______| | |
0.15| | |0.329|11.29| | | | | | | | | 324| 358| | | 118| 1.2| 43|
446| 127| |
|_______|______|_____|_____|_____|_____|____|___|_____|______| | |
0.20| | |0.399|13.66| | | | | | | | | 224| 247| | | 99| 1.4| 49|
351| 106|
|______________|_______|______|_____|_____|_____|_____|____|___|_____|______|
|Tertiary | 0.10| | |0.204| | | | | | | |Inferred | | 777| 856| |
7.01| 175| 0.3| 11| 282| 181| |
|_______|______|_____|_____|_____|_____|____|___|_____|______| | |
0.15| | |0.426|14.62| | | | | | | | | 219| 241| | | 103| 0.9| 30|
209| 107| |
|_______|______|_____|_____|_____|_____|____|___|_____|______| | |
0.20| | |0.593|20.33| | | | | | | | | 132| 146| | | 87| 1.2| 40|
171| 90|
|______________|_______|______|_____|_____|_____|_____|____|___|_____|______|
|Total | 0.10| 1|1 416|0.224| | | | | | | |Inferred | | 285| | |
7.68| 317| 0.6| 21| 872| 336| |RESOURCES
|_______|______|_____|_____|_____|_____|____|___|_____|______| | |
0.15| | |0.368|12.63| | | | | | | | | 543| 599| | | 221| 1.1| 37|
654| 235| |
|_______|______|_____|_____|_____|_____|____|___|_____|______| | |
0.20| | |0.471|16.14| | | | | | | | | 357| 393| | | 185| 1.3| 45|
521| 196|
|______________|_______|______|_____|_____|_____|_____|____|___|_____|______|
Notes: 1Gold equivalent ounces (Au eqv oz) were calculated by using
the following metal prices: US$1,400/oz for Au and US$30/oz for Ag.
Metallurgical recoveries are not applied to resource values;
contained metal estimates assume 100% recoveries. 2Parameters for
Measured = 50 feet (1/2 range), minimum number of informing samples
12; Indicated = 100 feet (1 x range), minimum number of informing
samples 8; Inferred = 750 feet (7.5 x range), minimum number of
informing samples 4. Exploration Progress Over the last year, work
has continued on the collation and review of all geophysical,
geological and surface drilling data for the property, with the
intent of better defining the basement structures that control
mineralization at Hollister. Detailed surface mapping has also
identified hydrothermal vent and eruptive centers - areas that
indicate the existence of long-lived geothermal activity and
potential additional deposition of Au-Ag mineralization at depth.
Targets outside the Clementine-Gwenivere vein systems have also
been delineated from this work, and will be prioritized for
follow-up. Drilling (which has been approved by the Bureau of Land
Management) is initially planned for the Hatter target (to upgrade
inferred resources to mineral resource status) and the Velvet -
Butte areas that locate north and north-west of the current
underground activity. The Hatter target requires a minimum of eight
boreholes to establish an additional Inferred mineral resource. The
mineralization at Hatter manifests as two distinct N-S and E-W vein
systems, which may indicate different phases of mineralizing
fluids. Mineral Reserves Within these mineral resources, mineral
reserves have been delineated that are available for mining as at
June 30, 2012, providing an update to the estimate in January 2011.
The mineral reserves have been estimated at a cut-off grade of 0.25
oz/t Au for the epithermal veins and 0.15 oz/t Au for the Tertiary
mineralization. The cut-off grades are based on an analyses of
fully diluted pay limit (break even) grades which incorporate a
gold and silver price of US$1400/oz and US$30/oz, respectively, and
estimated costs for mining, ore transport, milling, and royalties.
The break even grade for epithermal veins is 0.42 oz/t Au, and for
the Tertiary mineralization 0.25 oz/t Au. Mineral reserves
total 0.46 Mt grading on average 0.88 oz/t Au and 2.9 oz/t Ag
yielding 0.50 million Au eqv oz.
________________________________________________________________________
| | | | | | | | | | Au | Au | |Classification|Tonnes|Tons | Au | Au
|Au oz| Ag |Ag |Ag oz| eqv | eqv | | |(000) |(000)|oz/t | g/t
|(000)|oz/t|g/t|(000)|oz/t | oz | | | | | | | | | | | |(000)|
|______________|______|_____|_____|_____|_____|____|___|_____|_____|_____|
| Veins Proven| 90| |0.976|33.46| 98| 4.7|163| |1.078| | | | | 100|
| | | | | 474| | 108|
|______________|______|_____|_____|_____|_____|____|___|_____|_____|_____|
|Veins Probable| 266| 295|0.641|21.98| 189| 2.2| 76| |0.688| | | |
| | | | | | | 652| | 203|
|______________|______|_____|_____|_____|_____|____|___|_____|_____|_____|
| Tertiary| 109| 121|1.395|47.82| 168| 2.9| 98| |1.587| | |
Probable| | | | | | | | 344| | 191|
|______________|______|_____|_____|_____|_____|____|___|_____|_____|_____|
|Total Probable| 375| 416|0.860|29.48| 357| 2.4| 82| 996|0.950| | |
| | | | | | | | | | 394|
|______________|______|_____|_____|_____|_____|____|___|_____|_____|_____|
| TOTAL P & P | | | | | | | | | | | | RESERVES | 465|
516|0.882|30.26| 455| 2.9| 98|1 470|0.974| 502|
|______________|______|_____|_____|_____|_____|____|___|_____|_____|_____|
Notes: 1Mineral reserves are fully diluted, and grades adjusted for
metallurgical recoveries of Au (92%) and Ag (75%). 2Metal prices of
US$1,400 Au and US$30 Ag have been applied. It is important to note
that the mineral reserves only address that material available for
mining above the 4930 Level, which is the current lower development
level on the operation. The mining widths that have been planned
are believed to be achievable based on previous trial mining
activities on the epithermal vein system and the overlying Tertiary
volcanic "disseminated" style. The Tertiary mineralization occurs
in broad pod-like style zones of gold concentration that are
generally developed around very high grade, narrow structures,
sometimes linked to underlying epithermal veins. The maximum stope
design of 8 feet is considered very conservative, and, coupled with
the 10 foot pillar left around these areas, offers significant tons
and grade upside through mining method optimization. Considerable
upside exists with development of the Tertiary reserves as an
important ore source through a combination of maximizing access and
stoping options from the trackless infrastructure afforded by the
spiral ramp, as well as optimization of pillar/backfill designs,
which will maximize profitable extraction. Continued exploration
drilling in close proximity of the current mine infrastructure is
expected to extend the currently estimated minimum five year mine
life with additional vein structures delineated. Step-out drilling
targeted to increase the Mineral Resource of the project can be
accelerated once the Environmental Impact Study is completed which
is expected to occur this year The Company is currently preparing
an updated detailed mine schedule based on the updated
reserves A preliminary updated economic analysis of the
Nevada operations based on the updated reserves and using metal
prices of US$1,400 Au/oz and US$30 Ag/oz indicates a range of
after-tax net present values ("NPV") at June 30, 2012 of
approximately US$170 to US$190 million based on a 5% discount rate
and a five year life of mine. Increasing the gold price over the
life of mine to US$1,500/oz results in an NPV range of
approximately US$190 to US$210 million. Operational Performance
Nevada Preliminary production results for July and August 2012
indicate an improvement relative to the previous quarter with an
average of 6,500 Au eqv oz sold per month, compared to an average
of 5,000 Au eqv oz per month sold in Q2 2012. The 0.69 Au eqv oz/t
average grade from trial mining for July and August 2012 also
compares favorably to the 0.63 Au eqv oz/t trial mined in Q2 2012.
Further improvement is expected as additional higher grade stopes
from the tertiary material becomes available. The Esmeralda mill is
performing as planned with recoveries of 92% Au and 48% Ag thus far
for Q3 2012. Cash costs for Q3 2012 are expected to benefit from
the lower milling costs now that doré has been capable of being
poured on site since June 2012. Burnstone Ore development in July
and August 2012 averaged 888 meters per month, a 50% improvement on
the monthly average of 590 meters achieved in Q2 2012. The
improvements to the temporary water reticulation system reported on
earlier had a positive impact on ore development. The Company will
be taking over the underground waste development following the
termination of this contract with Grinaker Lta in August 2012,
which is expected to yield an estimated cost saving of $1.2 million
per month as well as improved efficiencies from development teams
and trackless equipment. Five thousand and fifty (5,050) square
meters was stoped during July and August 2012 with focus remaining
on development until phase 1 of the permanent water reticulation
system is completed by the end of September 2012. Shaft
availability has improved with the completion of the spillage
decline down to shaft bottom during August 2012. 180,000 tonnes at
an average head grade of 1.2 g/t were processed by the plant for
July and August 2012 with 4,280 ounces sold during the period. The
head grade of material delivered to the plant remains impacted by
the development/stoping ratio which is only expected to improve
once stoping increases later on in 2012. Strategic Review and
Liquidity Challenges The Special Committee of the Board continues
to evaluate refinancing and asset sell-down alternatives and is
endeavouring to work with all stakeholders to achieve an
acceptable resolution of its near term liquidity
challenges. A range of viable options remain possible
however the Company is not yet in a position to provide any
guidance as to if and when an announcement in this regard will be
made. Lou van Vuuren, interim CEO, commented: "Our ongoing
delineation drilling and trial mining results continue to confirm
the prospectivity of the Hollister property, and has also increased
our confidence in the reported resources and reserves. With the
completion in the June 2012 quarter of the Upper Zone spiral ramp
as well as 4930 Level, which provides a new access level to the
mine and the higher grade Clementine # 18 and 20 veins for trial
mining, the focus will continue to be on better delineation of
mineralization that is accessible from current underground
infrastructure. As underground development continues, there will be
further opportunities to drill-test for extensions to a number of
high grade zones that have been identified from the evaluation of
the Butte bounding-fault structure as well as Hatter Graben system.
Operationally we are seeing an improvement with more expected as
the Nevada operations return to planned production levels and
Burnstone completing the remaining critical infrastructure. The
Company continues to receive considerable interest in its projects
from qualified financiers and industry players and with the
information in this news release now having been disseminated we
will be in a position to accelerate our strategic process." The
mineral reserve estimates were completed by Martin Cooper, MGSSA,
and the mineral resource estimates by Freddie de Bruin and John
Murgatroyd, Pr.Sci.Nat., all of Deswik Mining and Resource
Consultants, under the supervision of Phil Bentley, Pr.Sci.Nat.,
Great Basin Gold's Vice President: Geology & Exploration and
Dana Roets, FSAIMM, Great Basin Gold's Chief Operating Officer,
both Qualified Persons as defined by Canadian National Instrument
43-101 (Disclosure Standards for Mineral Projects), who have
reviewed and approved the technical information in this news
release. Lou van Vuuren CEO (interim)
__________________________________________________________________
|Samples collected from the Hollister Development Block Project
are| |delivered to Inspectorate America Corporation (Inspectorate)
in | |Sparks, Nevada. |
|__________________________________________________________________|
Information Concerning Estimates of Measured, Indicated and
Inferred Resources This news release also uses the terms "measured
resources", "indicated resources" and "inferred resources". The
Company advises investors that although these terms are recognized
and required by Canadian regulations (under National Instrument
43-101 Standards of Disclosure for Mineral Projects), the U.S.
Securities and Exchange Commission does not recognize them.
Investors are cautioned not to assume that any part or all of the
mineral deposits in these categories will ever be converted into
SEC-recognised reserves. [Some are reserves under Canadian
standards.] In addition, 'inferred resources' have a great
amount of uncertainty as to their existence, and economic and legal
feasibility. It cannot be assumed that all or any part of an
Inferred Mineral Resource will ever be upgraded to a higher
category. Under Canadian rules, estimates of Inferred Mineral
Resources may not form the basis of feasibility or pre-feasibility
studies, or economic studies except for Preliminary Assessment as
defined under 43-101. Investors are cautioned not to assume that
part or all of an inferred resource exists, or is economically or
legally mineable. Cautionary and Forward Looking Statement
Information This document contains "forward-looking statements"
that were based on Great Basin's expectations, estimates and
projections as of the dates as of which those statements were made.
Generally, these forward-looking statements can be identified by
the use of forward-looking terminology such as "outlook",
"anticipate", "project", "target", "believe", "estimate", "expect",
"intend", "should" and similar expressions. Forward-looking
statements are subject to known and unknown risks, uncertainties
and other factors that may cause the Company's actual results,
level of activity, performance or achievements to be materially
different from those expressed or implied by such forward-looking
statements. These include but are not limited to: -- uncertainties
related to the Company's liquidity challenges and need for near
term financing -- uncertainties and costs related to the Company's
exploration and development activities, such as those associated
with determining whether mineral resources or reserves exist on a
property; -- uncertainties related to feasibility studies that
provide estimates of expected or anticipated costs, expenditures
and economic returns from a mining project; uncertainties related
to expected production rates, timing of production and the cash and
total costs of production and milling; -- uncertainties related to
the ability to obtain necessary licenses, permits, electricity,
surface rights and title for development projects; -- operating and
technical difficulties in connection with mining development
activities; -- uncertainties related to the accuracy of our mineral
reserve and mineral resource estimates and our estimates of future
production and future cash and total costs of production, and the
geotechnical or hydrogeological nature of ore deposits, and
diminishing quantities or grades of mineral reserves; --
uncertainties related to unexpected judicial or regulatory
proceedings; -- changes in, and the effects of, the laws,
regulations and government policies affecting our mining
operations, particularly laws, regulations and policies relating to
o mine expansions, environmental protection and associated
compliance costs arising from exploration, mine development, mine
operations and mine closures; o expected effective future tax rates
in jurisdictions in which our operations are located; o the
protection of the health and safety of mine workers; and o mineral
rights ownership in countries where our mineral deposits are
located, including the effect of the Mineral and Petroleum
Resources Development Act (South Africa); -- changes in general
economic conditions, the financial markets and in the demand and
market price for gold, silver and other minerals and commodities,
such as diesel fuel, coal, petroleum coke, steel, concrete,
electricity and other forms of energy, mining equipment, and
fluctuations in exchange rates, particularly with respect to the
value of the U.S. dollar, Canadian dollar and South African rand;
-- unusual or unexpected formation, cave-ins, flooding, pressures,
and precious metals losses (and the risk of inadequate insurance or
inability to obtain insurance to cover these risks); -- changes in
accounting policies and methods we use to report our financial
condition, including uncertainties associated with critical
accounting assumptions and estimates; -- environmental issues and
liabilities associated with mining including processing and stock
piling ore; -- geopolitical uncertainty and political and economic
instability in countries which we operate; and -- labour strikes,
work stoppages, or other interruptions to, or difficulties in, the
employment of labour in markets in which we operate mines, or
environmental hazards, industrial accidents or other events or
occurrences, including third party interference that interrupt the
production of minerals in our mines. For further information on
Great Basin Gold, investors should review the Company's annual Form
40-F filing with the United States Securities and Exchange
Commission www.sec.gov and home jurisdiction filings that are
available at www.sedar.com. Great Basin Gold Ltd. CONTACT: For
additional details on Great Basin Gold Ltd. and its goldproperties,
please visit the Company's website at www.grtbasin.com orcontact
Investor Services Michael Curlook, Head of Investor Services
at1-888-633-9332.
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