Pretium Resources Inc. (TSX:PVG)(NYSE:PVG) ("Pretivm") is pleased
to report the 2012 Valley of the Kings Mineral Resource estimate
for its wholly-owned Brucejack Project, completed by Snowden Mining
Industry Consultants ("Snowden") independent Qualified Persons.
Indicated Mineral Resources in the Valley of the Kings increased by
66% to 8.5 million ounces of gold at a cut-off grade of 5 grams of
gold equivalent per tonne since the interim September 7, 2012
Mineral Resource estimate.
Valley of the Kings High-Grade Gold Mineral Resources
High-grade gold resources in the Valley of the Kings (5.0 g/t
gold-equivalent cut-off) total:
-- 8.5 million ounces of gold in the Indicated Mineral Resource category
(16.1 million tonnes grading 16.4 grams of gold per tonne); and
-- 2.9 million ounces of gold in the Inferred Mineral Resource category
(5.4 million tonnes grading 17.0 grams of gold per tonne).
The Mineral Resource estimate incorporates data from all
drilling to date, including 2012 drilling comprising 99,632 meters
in 270 drill holes targeted at the Valley of the Kings. Recent
geological interpretation shows Galena Hill to be an extension of
the Valley of the Kings. Accordingly, Galena Hill drilling and
Mineral Resources have been incorporated into the Valley of the
Kings. Galena Hill comprises 6,284 meters in 14 holes of the total
2012 drilling noted above (plus historical drilling), and
contributes 574,000 ounces of gold to the 2012 Valley of the Kings
Indicated Mineral Resource. An isometric view of the Valley of the
Kings block model is available at
http://media3.marketwire.com/docs/pvg20-VOK.pdf.
The Indicated Mineral Resource is defined over approximately 600
meters of the total strike length of the Valley of the Kings, which
now extends to over 1,000 meters. In addition to the potential of
the defined strike length not incorporated into the Indicated
Mineral Resource, the Valley of the Kings remains open to the east
and west along strike and at depth. A plan view of the Valley of
the Kings highlighting the Indicated Mineral Resource is available
at http://media3.marketwire.com/docs/pvg20-plan.pdf.
Table 1: Valley of the Kings Mineral Resource estimate - November 2012(1)(4)
(Based on a cut-off grade of 5.0 grams of gold-equivalent/tonne(5))
----------------------------------------------------------------------------
Contained(3)
----------------------------
Tonnes Gold Silver Gold Silver
Category (millions) (g/t) (g/t) (million oz) (million oz)
----------------------------------------------------------------------------
Indicated 16.1 16.4 14.2 8.5 7.3
----------------------------------------------------------------------------
----------------------------------------------------------------------------
Inferred(2) 5.4 17.0 15.7 2.9 2.7
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(1) Mineral Resources which are not Mineral Reserves do not have
demonstrated economic viability. The estimate of Mineral Resources may be
materially affected by environmental, permitting, legal, marketing, or
other relevant issues. The Mineral Resources in this news release were
estimated using the Canadian Institute of Mining, Metallurgy and Petroleum
(CIM), CIM Standards on Mineral Resources and Reserves, Definitions and
Guidelines prepared by the CIM Standing Committee on Reserve Definitions
and adopted by CIM Council.
(2) The quantity and grade of reported Inferred resources in this estimation
are uncertain in nature and there has been insufficient exploration to
define these Inferred Resources as an Indicated or Measured Mineral
Resource and it is uncertain if further exploration will result in
upgrading them to an Indicated or Measured Mineral Resource category.
(3) Contained metal figures and totals may differ due to rounding of
figures.
(4) The Mineral Resource estimate stated in Table 1 is defined using 10 m by
10 m by 10 m blocks in the in Valley of the Kings.
(5) The gold equivalent value is defined as AuEq = Au + Ag/53.
Mineral Resource Modeling and Estimation
The November 2012 Mineral Resource estimates for Valley of the
Kings were completed by Snowden on behalf of Pretivm. The Mineral
Resources are classified as Indicated and Inferred Resources in
accordance with the CIM Standards on Mineral Resources and
Reserves, Definitions and Guidelines prepared by the CIM Standing
Committee on Reserve Definitions and adopted by CIM Council.
Classification is applied based on geological confidence, data
quality and grade variability. Areas classified as Indicated
Resources are informed by 20 meter by 20 meter to 20 meter by 40
meter drilling. With respect to some of the areas in the high grade
zones at the Valley of the Kings that have drill spacing nearing
that of the Measured Resource previously reported at West Zone,
Snowden has elected to retain the Indicated Resource classification
until underground sampling has demonstrated a high level of
confidence in these estimates. This is because of the high-grade
nature of the mineralization. The remainder of the Mineral Resource
is classified as an Inferred Resource where there is some drilling
information and the blocks lie within the mineralised
interpretation. Areas where there is no informing data and/or the
lower grade material that is outside of the mineralised
interpretation are not classified as a part of the Mineral
Resource.
The Mineral Resources are reported above a cut-off grade of 5.0
grams of gold-equivalent/tonne (5.0 g/t AuEq). The gold-equivalent
calculation used is: Au + (Ag/53).
The Brucejack Property comprises several gold-silver mineralised
areas. These areas include West Zone, Valley of the Kings, Galena
Hill, Bridge Zone, Gossan Hill and Shore Zone. The majority of the
Mineral Resource lies within Valley of the Kings and West Zone.
West Zone, Gossan Hill, Shore Zone and Bridge Zone were not updated
for this Mineral Resource as there has been little additional
drilling in these areas. The focus of the 2012 drilling has been on
the high grade Valley of the Kings and Galena Hill areas. Recent
geological interpretation shows that the area previously covered by
Galena Hill is actually an extension of Valley of the Kings, and
this area has now been incorporated into Valley of the Kings.
The Valley of the Kings mineralisation is approximately 500
meters south of West Zone. The Valley of the Kings mineralized zone
trends approximately west-northwest to east-southeast. Its
orientation mirrors that of Electrum Ridge, a pronounced
topographic feature near the southern margin of the zone, and
drilling to date has extended its strike to over 1,000 meters. The
zone is up to 170 meters wide and remains open to the west, beyond
the Brucejack fault, at depth and to the east. Surface mapping and
Pretivm's extensive drilling defined a number of lithologic
contacts which outline a broad syncline in which fragmental
volcanic and clastic sedimentary rocks, along with minor flows of
Upper Triassic to Lower Jurassic age appear to plunge moderately to
the east.
Pretivm used their interpretation of the lithological units at
the Valley of the Kings, together with a nominal 1 to 3 g/t Au
grade cut-off to update the mineralised domains for estimation at
the Valley of the Kings.
The input data for the Valley of the Kings estimate comprises
490 drillholes for 174,182 meters including 9 historical surface
drillholes (579 meters) and 114 surface drillholes completed since
the previous September 2012 Mineral Resource (46,944 meters). These
figures exclude intervals with no gold values and drillholes
outside of the Valley of the King area.
The Valley of the Kings exhibits extremely skewed grade
populations where the high grades and the majority of the metal are
located in less than 5% of the data, with individual raw gold
grades of up to around 41,500 g/t Au. Discussions with Pretivm and
analysis of the data indicated the mineralisation can be split into
a pervasive background mineralisation and a separate high-grade but
discreet mineralisation style. As a result of this population
distribution, standard estimation techniques have been found to
significantly over smooth the grades.
In order to address the highly skewed nature of the data,
Snowden separated the lower grade 'background' population from the
higher grade population within these domains and estimated them
independently. All data was composited to the nominal sample length
of 1.5 meters prior to analysis and estimation. A threshold of 5
g/t Au was selected to separate the two populations at the Valley
of the Kings. The silver data was treated using the same method
with a threshold of 50 g/t Ag for Valley of the Kings.
The lower grade population was estimated using ordinary kriging
into 10 meter by 10 meter by 10 meter parent blocks. This estimate
validates well against the input data.
The higher grade populations were estimated using multiple
indicator kriging to control the skewness of the data. Indicator
variograms were modelled up to the 95th percentile of the data with
a mathematical model used to define the top end of the grade
distribution. The threshold for the 95th percentile of the higher
grade population is 421 g/t Au for the Valley of the Kings. The
result of this estimation method is that, while no top cut is used
to limit the higher grades, the higher grades are limited in their
influence using a mathematical model based on the higher grade data
rather than the individual extreme grades in the dataset. The
higher grade populations were estimated into small scale
discretized blocks and then reblocked into parent blocks twice the
size of those used for the lower grades to further limit the
influence of the highest grades in the highest grade areas.
Subsequently, the proportion of the higher-grade mineralisation
was estimated into each block and used to combine the two estimates
(the low grade portion and the high grade portion) in the
determination of the overall block grade. For example, if a block
had a probability of 5% high grade then the final block grade would
combine 95% of the low grade estimate with 5% of the high grade
estimate. The influence of the high-grade population above the 95th
percentile is therefore greatly restricted.
The background (non-mineralised) material was estimated using
ordinary kriging with a top cut.
The database used to estimate density is based on pulp specific
gravity measurements. As part of the 2012 drilling program,
Pretivm's QP selected a portion of the samples (207 samples) to
undergo core density measurements as well as pulp specific gravity
measurements in order to determine whether there is any impact on
the density as a result of porosity. The results of the comparison
indicate that the core density is on average 6% lower than the pulp
specific gravity within the siliceous zone and 9% lower on average
in all other rock types. As a result the pulp specific gravity
measurements, which are used to estimate density in the model, were
factored by 6% (siliceous zone) or 9% (other rock types) prior to
estimation. Tonnages were estimated on a dry basis with density
values estimated into the models using simple kriging where
sufficient data was available. Outside of these areas, the average
density of 2.54 t/m3 was applied. There is little variation in
density between the different rock types.
The updated Mineral Resource estimate for the Valley of the
Kings is significantly higher in confidence than the previous
September 2012 estimate as a result of almost twice the amount of
drillhole composites within the mineralised corridors. This
additional data has resulted in higher confidence in the geological
interpretation used in the estimation. The additional drilling
confirms the location of the high-grade corridors and has allowed a
better estimate of the boundaries of these corridors in areas where
there was insufficient data to confirm the location of boundaries
previously. The additional confidence has allowed an increase in
the amount of material classified as Indicated, with much of the
higher grade material previously classified as Inferred, now
incorporated into the Indicated Resource. In addition the
additional drilling to the east and west of the previously defined
mineralised corridors, has allowed an expansion of the Inferred
Resource into these areas.
Bulk Sample; Feasibility Study
Pretivm has commenced an underground exploration program
designed, amongst other things, to access the Valley of the Kings
underground and demonstrate continuity of the high-grade gold
mineralization. The first phase, now well underway, is to slash out
the existing West Zone underground workings to five-by-five meters
then excavate a decline from the West Zone to the Valley of the
Kings, a distance of approximately 450 meters. We are currently
planning the sampling and mining plans for a 10,000 tonne
underground bulk sample, which we expect to excavate from the
Valley of the Kings in the second quarter of 2013.
Also underway is a feasibility study for an underground mine
with an operating rate of 2,700 tonnes per day using a mining
method of long-hole stoping and cemented paste backfill. Stopes
will be mined using a combination of longitudinal and transverse
mining, depending on zone width and orientation. Cemented paste
tailings will be prepared in a paste plant located on surface near
the mill and then pumped underground for distribution to the
stopes.
With the 66% increase in the Indicated Mineral Resource at the
Valley of the Kings, Pretivm plans to incorporate the updated
Mineral Resource in the feasibility study. The feasibility study is
currently expected to be completed in the second quarter of 2013,
and we will advise in due course on the impact to the schedule.
Independent Qualified Persons
The above table summarizes the high-grade Mineral Resource
estimate totals for the Valley of the Kings zone of the Brucejack
Project. The Mineral Resource estimate contained in this news
release was prepared by Ivor Jones (FAusIMM(CP)) and Lynn Olssen
(MAusIMM(CP)) of Snowden, both of whom are independent Qualified
Persons, as defined by National Instrument 43-101. Mr. Jones and
Ms. Olssen have reviewed and approved the contents of this news
release.
Snowden delivers a comprehensive range of technical consulting
services, independent advice and technology solutions to the mining
sector. Snowden's areas of expertise cover both open pit and
underground mining operations, for the majority of mineral
commodities, with projects ranging from exploration and resource
evaluation to mine planning, metallurgy, and mine optimisation.
Snowden was established 25 years ago in Perth, Australia, and has
eight offices located in the world's major mining regions.
About Pretivm
Pretivm is creating value through gold at its high-grade gold
Brucejack Project, located in northern British Columbia. Brucejack
hosts a major undeveloped high-grade gold resource and
mineralization remains open in all directions. A feasibility study
for a high-grade underground mine in Brucejack's Valley of the
Kings is underway and expected in the second quarter of 2013.
Forward-Looking Statements
This News Release contains "forward-looking information" and
"forward-looking statements" within the meaning of applicable
Canadian and United States securities legislation. Forward-looking
information may include, but is not limited to, risks related to
our planned exploration and development activities, the adequacy of
Pretivm's financial resources, the estimation of mineral resources,
realization of mineral resource estimates, timing of development of
Pretivm's Brucejack Project, costs and timing of future
exploration, results of future exploration and drilling, production
and processing estimates, capital and operating cost estimates,
timelines and similar statements relating to the economic viability
of the Brucejack Project, timing and receipt of approvals, consents
and permits under applicable legislation, Pretivm's executive
compensation approach and practice, and adequacy of financial
resources. Wherever possible, words such as "plans", "expects",
"projects", "assumes", "budget", "strategy", "scheduled",
"estimates", "forecasts", "anticipates", "believes", "intends" and
similar expressions or statements that certain actions, events or
results "may", "could", "would", "might" or "will" be taken, occur
or be achieved, or the negative forms of any of these terms and
similar expressions, have been used to identify forward-looking
statements and information. Statements concerning mineral resource
estimates may also be deemed to constitute forward-looking
information to the extent that they involve estimates of the
mineralization that will be encountered if the property is
developed. Any statements that express or involve discussions with
respect to predictions, expectations, beliefs, plans, projections,
objectives, assumptions or future events or performance are not
statements of historical fact and may be forward-looking
information. Forward-looking information is subject to a variety of
known and unknown risks, uncertainties and other factors that could
cause actual events or results to differ from those expressed or
implied by the forward-looking information, including, without
limitation, those risks identified in Pretivm's prospectus
supplement to the short form base shelf prospectus dated March 19,
2012 filed on SEDAR at www.sedar.com and in the United States
through EDGAR at the SEC's website at www.sec.gov. Forward-looking
information is based on the expectations and opinions of Pretivm's
management on the date the statements are made. The assumptions
used in the preparation of such statements, although considered
reasonable at the time of preparation, may prove to be imprecise.
We do not assume any obligation to update forward-looking
information, whether as a result of new information, future events
or otherwise, other than as required by applicable law. For the
reasons set forth above, prospective investors should not place
undue reliance on forward-looking information.
(SEDAR filings: Pretium Resources Inc.)
The TSX has neither approved nor disapproved of the information
contained herein.
Contacts: Pretium Resources Inc. Robert Quartermain President
and Chief Executive Officer (604) 558-1784 Pretium Resources Inc.
Michelle Romero Corporate Relations Director (604)
558-1784invest@pretivm.com www.pretivm.com
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