Great Western Minerals Group announces an increase in the mineral
resource estimate on Steenkampskraal rare earth deposit, South
Africa
TSX Venture Symbol: GWG
OTCQX: GWMGF
CUSIP: 39141Y 10 3
SASKATOON, Jan. 21,
2013 /PRNewswire/ - Great Western Minerals Group Ltd.
("GWMG" or the "Company", TSX:V - GWG) today announced that
its updated National Instrument 43-101 resource estimate and
technical report (the "NI 43-101 Report") shows a significant
increase in the mineral resource (both Indicated and Inferred
categories) compared to the Company's previously released NI 43-101
report of May 18, 2012.
The updated NI 43-101 Report, which has been
prepared by Snowden Mining Industry Consultants Inc. ("Snowden")
for the Company's Steenkampskraal rare earth property located in
the Western Cape of South Africa,
is dated effective December 15, 2012
and will be filed and available under the Company's SEDAR profile
at www.sedar.com within 45 days.
Highlights:
- A mineral resource estimate of 32,000 metric tonnes of total
rare earth oxides plus yttrium oxide ("TREO") under the Indicated
category and 42,100 metric tonnes of TREO under the Inferred
category, each using a 1% TREO cut-off grade (the "Resource
Estimate").
- The new results demonstrate the success of GWMG's exploration
programs at Steenkampskraal with a 114% increase in the Indicated
Resource and a 218% increase in the Inferred Resource as compared
to May of 2012.
- The drilling program continues at Steenkampskraal with goals
of: expanding the Resource Estimate; increasing the confidence in
the geological model, upgrading the categories of reported
resources; providing technical data for mine planning; and to check
for mineralisation in those areas of the property where the
concentrator and other infrastructure facilities will be
located.
- The core logging and assay results of 55 completed drillholes
remain to be evaluated and reported in a future update.
Resource Estimate
This Resource Estimate, which incorporates and
supersedes that reported on May 31,
2012, indicates a significant increase in tonnage of the
deposit primarily as a function of increased drilling along strike
to the East (as shown in Table 1, below). The Resource
Estimate includes the historic mine area (the "Monazite Mine
Area"), the exploration areas to the east and west of the past
producing Monazite Mine Area (the "EXP Area") and the upper and
lower tailings dams.
Table 1: Updated Mineral Resource Estimate for
Steenkampskraal at a 1% cut-off grade (as of October 31, 2012)
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Updated Resource Estimate1 |
|
Monazite
Tonnes |
|
Average
TREO% |
|
Contained
TREO tonnes |
|
LREO2
tonnes |
|
HREO2
tonnes |
|
Monazite Mine
Area |
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Indicated |
|
71,500 |
|
23.0 |
|
16,400 |
|
15,200 |
|
1,260 |
|
|
Inferred |
|
95,800 |
|
17.1 |
|
16,400 |
|
15,100 |
|
1,270 |
|
EXP Area |
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Indicated |
|
68,200 |
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18.1 |
|
12,400 |
|
11,400 |
|
970 |
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|
Inferred |
|
181,000 |
|
14.2 |
|
25,600 |
|
23,500 |
|
2,100 |
|
Upper
Tailings |
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Indicated |
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8,000 |
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9.3 |
|
700 |
|
700 |
|
60 |
|
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Inferred |
|
1,200 |
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7.5 |
|
100 |
|
100 |
|
10 |
|
Lower
Tailings |
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Indicated |
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28,600 |
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8.8 |
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2,500 |
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2,300 |
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210 |
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Inferred |
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0 |
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0 |
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0 |
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0 |
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Category Totals for Updated
Resource |
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Indicated |
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176,000 |
|
18.2 |
|
32,000 |
|
29,600 |
|
2,500 |
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Inferred |
|
278,000 |
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15.2 |
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42,100 |
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38,700 |
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3,400 |
Previous (May 2012)
estimate |
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Total (Monazite
Mine Area,
Upper and Lower Tailings) |
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Indicated |
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82,090 |
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16.8 |
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13,800 |
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12,700 |
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1,100 |
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Inferred |
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87,160 |
|
16.2 |
|
14,100 |
|
13,100 |
|
1,100 |
(1) For the updated Resource Estimate,
"tonnes" and "grades" were rounded to 3 significant figures.
Apparent errors may occur due to rounding.
(2) "LREO" means lanthanum (La2O3), cerium
(CeO2), praseodymium (Pr6O11), neodymium (Nd2O3) and samarium
(Sm2O3). "HREO" means europium (Eu2O3), gadolinium (Gd2O3),
terbium (Tb4O7), dysprosium (Dy2O3), holmium (Ho2O3), thulium
(Tm2O3), ytterbium (Yb2O3) lutetium (Lu2O3) and yttrium (Y2O3).
The additional drilling completed since May of
2012 has provided significantly more density measurements which has
yielded an increase in the calculated average specific gravity of
the deposit from 3.23 g/cm3 to 3.50
g/cm3.
Table 2 shows a summary of individual REO
results for the in-situ Mine and EXP Areas, which were the focus of
the updated Resource Estimate. Complete Resource Estimate
results for individual REOs will be available in the NI 43-101
Report once filed on SEDAR.
Table 2: Updated Mineral Resource Estimate of REO Percentage
for the Mine and EXP Areas at Steenkampskraal using a 1% cut-off
grade (as of October 31,
2012)
Area |
Resource
Category |
Y2O3
% |
La2O3
% |
CeO2
% |
Pr6O11
% |
Nd2O3
% |
Sm2O3
% |
Eu2O3
% |
Gd2O3
% |
Tb4O7
% |
Dy2O3
% |
Ho2O3
% |
Er2O3
% |
Tm2O3
% |
Yb2O3
% |
Lu2O3
% |
Mine |
Indicated |
0.91 |
4.780 |
10.500 |
1.180 |
4.100 |
0.643 |
0.014 |
0.436 |
0.052 |
0.221 |
0.033 |
0.065 |
0.006 |
0.025 |
0.003 |
Inferred |
0.69 |
3.530 |
7.830 |
0.887 |
3.090 |
0.484 |
0.010 |
0.326 |
0.038 |
0.166 |
0.025 |
0.049 |
0.005 |
0.019 |
0.002 |
Exploration |
Indicated |
0.73 |
3.820 |
8.130 |
0.926 |
3.310 |
0.513 |
0.011 |
0.357 |
0.042 |
0.174 |
0.026 |
0.052 |
0.005 |
0.020 |
0.002 |
Inferred |
0.6 |
2.990 |
6.320 |
0.725 |
2.600 |
0.408 |
0.011 |
0.280 |
0.034 |
0.143 |
0.021 |
0.045 |
0.005 |
0.020 |
0.003 |
Indicated Total |
0.83 |
4.311 |
9.343 |
1.056 |
3.714 |
0.580 |
0.012 |
0.397 |
0.047 |
0.198 |
0.030 |
0.059 |
0.006 |
0.023 |
0.002 |
Inferred Total |
0.63 |
3.177 |
6.844 |
0.781 |
2.770 |
0.434 |
0.011 |
0.296 |
0.036 |
0.151 |
0.023 |
0.046 |
0.005 |
0.020 |
0.003 |
GWMG President and Chief Executive Officer
Marc LeVier said, "The substantial
increase in TREO tonnage from this Resource Estimate update
significantly improves the economic potential of the
Steenkampskraal Monazite Project. The resource update reported
today will be incorporated into the Preliminary Economic Assessment
that is being prepared concurrently. We expect the
Steenkampskraal analysis will be bolstered further with the
upcoming addition of a minimum of 55 drillholes for which assay
work is currently in progress."
Geology and Mineralization
The Steenkampskraal mineralization consists of a
narrow, shallow and irregular dipping (from 10o to
60o to the south), pinch and swell monazite vein which
is exposed at surface as an east-west striking body (the "MMZ"). It
has an average thickness of about 1.0 metre ("m"), varying from
less than 20 centimetres ("cm") to 9.5m. The vein has been traced
for a strike-length of just over 1,050m and a known southerly
down-dip extension of up to 150m. The Resource Estimate covers a
strike length of about 920m. The vein structure exhibits good
lateral and vertical continuity. Mineralization is open on
strike in both directions and down-dip below a depth of 130m along
most of the strike length explored to date.
Mineralogical investigations indicate that the
vein is composed predominantly of the mineral monazite, which
accounts for more than 91% of total rare earth elements, with
lesser amounts of rare earth element-bearing allanite, thorite, and
xenotime. Alteration minerals are dominated by quartz,
Fe-chlorite, magnetic Fe-oxide minerals, ilmenite, and sulphides
including chalcopyrite, pyrite and galena. Vein material at
Steenkampskraal contains from 0.4% to 46% TREO with the average
grade typically dependent on the amount of diluting materials (such
as quartz, feldspar, magnetite and sulphides) within the vein
structure.
Exploration
The historic Steenkampskraal mine has been
partially rehabilitated by GWMG and all three access levels and
most of the old workings are open to geological and geotechnical
investigations. Evaluation and exploration work from
September 2011 to December 2012 consisted of surveying, mapping 67
underground channel samples and199 HQ and NQ surface drillholes
totalling 23,305.31m within the Mine and the EXP Areas. In
addition, GWMG undertook evaluation drilling and sampling of the
historic tailings dams. The rock dump has also been sampled, but
has not yet been included in the resource estimates.
The May, 2012 estimate reported on 40 initial
evaluation and metallurgical drillholes from the Monazite Mine
Area, the first two exploration drillholes in the EXP Area, and
sampling of the tailings dams. Subsequent to this
investigation, an additional 157 HQ and NQ size core holes were
completed in the EXP Area. Of these, EXP Area drillholes
STKEXP-003 to STKEXP-105 have been added to the geological model
and Resource Estimate which form the basis for the current NI
43-101 Report. Drillhole survey information, intercept
thicknesses, lithological descriptions, density measurements,
scintillometer readings, and assay results for drillholes
STKEXP-003 to STKEXP-067 are included in the current NI 43-101
Report, as well as similar information for drillholes STKEXP-068 to
STKEXP-105 (other than assay results) which were received after
the data cut-off date.
Of the 105 exploration drillholes (STKEXP-001 to
STKEXP-105) reviewed by Snowden, 27 did not intersect the MMZ. The
reported "misses" represent either drilling beyond the vein
boundaries, or local areas of non-mineralization within the "pinch
and swell" vein system. Drillhole fence lines are oriented along
down-dip lines perpendicular to strike on nominal 25m to 50m line
spacing, and 25m collar centers. The western, eastern
and down-dip extensions of the MMZ remain open to date.
Drillholes STKEXP-106 to STKEXP-159 will be included in a future
report.
Quality Assurance / Quality Control
("QA/QC")
Caracle Creek International Consultants (Pty)
Ltd ("CCIC") examined the assay data of the blanks, certified
reference materials, and field duplicates to assess the reliability
of the overall assay dataset, and to assist in the determination of
the robustness of the resource estimation that has been carried out
using the assay results. Addition of quality control samples for
all core, channel and tailings samples amounts to 30% representing
approximately 10% each for blanks, duplicates, and standard
references. It was concluded by CCIC in general, that the
addition of reference material and blanks to the Steenkampskraal
sample batches was sufficiently adequate.
The validated database for the Resource Estimate
includes information on 569 samples from 145 diamond drillholes of
which 88 drillholes contained assay data using a September 2012 data cut-off date. Drill
holes that did not contain assay data were included as they
provided lithological information for the wireframe modelling and
radiometric data was used for potential grade interpolation. The
database also included information for 223 samples from a total of
67 underground channel sections and 270 tailings samples.
Table 3: Comparison of May 2012 and current databases used for the
in-situ Resource Estimate
Sample
Type |
May
2012 Database |
Current Database |
Number
Drilled/Cut |
Number
Sampled |
Number
Drilled/Cut |
Number
Sampled |
Diamond Drill |
107 |
44 |
145 |
88 |
Channel |
67 |
59 |
67 |
67 |
Limited Grade Estimation using the
Scintillometer / TREO% Relationship
REE-bearing minerals at Steenkampskraal have
associated thorium and uranium content and subsequent
radioactivity. Radiation measurements in counts per second
using a Terraplus RS-125 Gamma Ray Spectrometer were acquired for
all samples that were submitted for assay from 127 drillholes and
32 out of 67 channel samples.
There is a strong positive association
(correlation coefficient of approximately 0.95) between TREO grade
from assay results and radioactivity as defined using detailed
scintillometer measurements. The linear formula generated by
the correlation was subsequently applied to obtain an indicative
TREO% in all drillholes that have been sampled, have radiometric
measurements, and are awaiting assays.
In the absence of chemical assays, it is
Snowden's considered opinion that because of the strong
relationship between the scintillometer measurements and the TREO
grades at Steenkampskraal, the application of the
TREO-radioactivity correlation is sufficiently reliable to estimate
"calculated and inferred" grades for the drillholes missing assay
values at a low to moderate level of confidence, and that these
values are suitable for use in the estimation of an Inferred
Resource.
Modelling and Estimation Method
The mineralized zone wireframe, representing the
MMZ, was generated using Leapfrog™ software after much verification
work, based on drill intersections of the MMZ and guided by the
available geological information. All of the assay intervals
falling within the MMZ were composited to the dominant sample
length of 0.5m.
Establishment of Block Models and Variography
Analysis
The interior of the MMZ wireframe was populated
with blocks measuring 10m by 10m by 0.5m using
Datamine™ Studio version 3 software. Sub-blocking was used to
provide for a more accurate volume determination; the smallest
dimension for sub-blocks being 1.25 m by 1.25 m by 0.1 m. No
rotation of blocks was applied as the strike and dip of the
monazite was honoured through the small dimensions of
sub-blocking.
Variograms were generated for each of the rare
earth oxides ("REOs") as well as yttrium, thorium and uranium, and
only using the assay data from the MMZ. Spherical, two
structured, directional variogram models were used. Down-hole
variograms were calculated and modelled to determine the nugget
variance for the variogram models. The data occurring within the
MMZ wireframes were combined for the three main zones to generate
more robust variograms. The nugget, determined from the
down-hole variogram, ranges from 28% to 35% of the total variance
of the data. The variograms showed well developed structure and
long ranges.
The combined block model (unclassified and
depleted) comprises 8,358 indicative value estimated blocks out of
40,702 total blocks. None of the blocks estimated using the
indicative data are reported as part of the Indicated Resource.
Grade Interpolation Parameters
Block grades for the individual REOs, yttrium,
thorium and uranium were estimated using ordinary kriging. Four
domains were delineated based on the location of major faults, and
a small area of complexity characterized by bifurcation or
interleaving of several monazite veins. The zones were
estimated separately and individual block models combined for
classification.
TREO%, LREO% and HREO% values, which were
calculated for reporting by combining the estimated grades of the
individual REOs, were also estimated in the block model as a check
to ensure the preservation of the total package and for validation,
but these were not reported.
The final block model was a combination of two
estimates; initially using composited assay data to estimate the
blocks, and secondarily using the composited assay data as well as
composited radiometric generated indicative grades (from drill
holes where mineralization was logged and sampled but awaiting
assays).
Density values were estimated into the block
model using the Inverse Distance ("ID") estimation method. ID
was used because there were insufficient drillholes with density
values to form structured variograms.
The block model was depleted for 'past
production' using current survey information pertaining to the
underground development and mined-out areas. This ensured
that stopes and development workings were not included in the
Resource Estimate.
Previous Resource Estimate for Tailings
Dams
The Resource Estimate restates the resources in
respect of the tailings dams, the results of which remain unchanged
from the May 2012 estimate. A
gridding approach was used to sample the tailings dams with sample
holes at 10m spacing over the extent of the two tailings dams.
Samples were collected on a per metre basis using a "Shelby tube"
that was manually driven into the tailings to the base of the pile.
The larger of the tailings dams contained material up to 2m thick
and the smaller dam up to 4m thick. Sample material from each
station, and each metre depth, were divided in a three level
riffle-splitter to make representative sub-samples for independent
grade analysis by SGS Canada and metallurgical studies by Mintek
Analytical Services Division. This procedure was subject to the
same QA/QC as for the drill core. The database of the
tailings dams comprised information from 270 drill samples.
Qualified Persons
The NI 43-101 Report was prepared by Mr.
Ivor Jones, (BSc. Hons), MSc,
FAusIMM, CP Geo., the Group General Manager of Geosciences with
Snowden. He contributed to and supervised the Resource
Estimate for the main monazite deposit as well as the tailing
dams. Mr. Jones consents to the inclusion in this news
release of the matters based on his information in the form and
context in which it appears. Mr. Jones has sufficient experience
relevant to the type of deposit under consideration and to the
activity which he is undertaking to qualify as a Qualified Person
as defined under NI 43-101 - Standards of Disclosure for Mineral
Projects ("NI 43-101") and supervised the preparation of the
contents of the Resource Estimate section of this news release.
Snowden was assisted by Dr. John Hancox, Pr.Sci.Nat., of Caracle Creek
International Consulting (Pty) Limited of Johannesburg. Dr. Hancox provided geological
interpretations and the drillhole and underground channel sampling
database for the Resource Estimate. Dr. Hancox has sufficient
experience relevant to the style of mineralization and type of
deposit under consideration and to the activity which he is
undertaking to qualify as a Qualified Person as defined under NI
43-101 and supervised the preparation of the contents of the
geology, exploration, and data assurance sections of this news
release. Dr. Hancox consents to the inclusion in this news release
of the matters based on his information in the form and context in
which it appears.
Brent C.
Jellicoe, B.Sc. (Hon.), P.Geo., Director of International
Exploration for GWMG, is the Qualified Person responsible for
supervising the preparation of the technical content of this news
release.
About Great Western Minerals Group
Ltd.
Great Western Minerals Group Ltd. is engaged in
becoming an integrated rare earth producer. Its specialty alloys
are used in the battery, magnet and aerospace industries. Produced
at the Company's wholly owned subsidiaries Less Common Metals
Limited in Ellesmere, U.K. and Great Western Technologies Inc. in
Troy, Michigan, these alloys
contain transition metals including nickel, cobalt, iron and rare
earth elements. As part of the Company's vertical integration
strategy, GWMG also holds 100% equity ownership in Rare Earth
Extraction Co. Limited, which controls the Steenkampskraal monazite
mine. In addition to an exploration program at Steenkampskraal,
GWMG also holds interests in four active rare earth exploration and
development properties in North
America.
Neither TSX Venture Exchange nor its Regulation
Services Provider (as that term is defined in the policies of the
TSX Venture Exchange) accepts responsibility for the adequacy or
accuracy of this release.
Cautionary Statements
Certain information set out in this News Release
constitutes forward-looking information. Forward-looking
statements (often, but not always, identified by the use of words
such as "expect", "may", "could", "anticipate" or "will" and
similar expressions) may describe expectations, opinions or
guidance that are not statements of fact and which may be based
upon information provided by third parties. Forward-looking
statements are based upon the opinions, expectations and estimates
of management of GWMG as at the date the statements are made and
are subject to a variety of known and unknown risks and
uncertainties and other factors that could cause actual events or
outcomes to differ materially from those anticipated or implied by
such forward-looking statements. Those factors include, but are not
limited to, risks associated with the uncertainty of resource
estimates, in particular those relating to Inferred
resources; risks relating to estimating grades, in particular
where interpolation is used to estimate grades; the successful and
timely completion of its preliminary economic assessment at Hoidas
Lake; the successful and timely completion and the results of its
preliminary economic assessment of the Steenkampskraal project; the
construction, commissioning and operation of the proposed monazite
processing facility and separation facility and mine refurbishment
activities; the adequacy of the Company's financial resources and
the availability of additional cash from operations or from
financing on reasonable terms or at all; reliance on third parties
to meet projected timelines and commencement of production at
Steenkampskraal; risks related to the receipt of all required
approvals including those relating to the commencement of
production at the Steenkampskraal mine, delays in obtaining
permits, licenses and operating authorities in Canada, South
Africa and China,
environmental matters, water and land use risks; risks associated
with the industry in general, commodity prices and exchange rate
changes, operational risks associated with exploration, development
and production operations, delays or changes in plans; health and
safety risks; uncertainty of estimates and projections of
production, costs and expenses; risks that future Hoidas Lake or
Steenkampskraal and region exploration results may not meet
exploration or corporate objectives; political risks inherent in
South Africa and China; risks associated with the relationship
between GWMG and/or its subsidiaries and communities and
governments in Canada and
South Africa, radioactivity and
related issues, dependence on one mineral project; loss of, and the
inability to attract, key personnel; the factors discussed in the
Company's public disclosure record; and other factors that could
cause actions, events or results not to be as anticipated. In light
of the risks and uncertainties associated with forward-looking
statements, readers are cautioned not to place undue reliance upon
forward-looking information. Although GWMG believes that the
expectations reflected in the forward-looking statements set out in
this press release or incorporated herein by reference are
reasonable, it can give no assurance that such expectations will
prove to have been correct. Except as required by law, GWMG does
not assume any obligation to update forward-looking statements as
set out in this news release. The forward-looking statements of
GWMG contained in this News Release, or incorporated herein by
reference, are expressly qualified, in their entirety, by this
cautionary statement and the risk factors contained in GWMG's
Professional Securities Market listing particulars available at
www.sedar.com.
Cautionary Note For US Investors Concerning
Estimates of Indicated and Inferred Resources
This press release uses the terms "Indicated"
and "Inferred" resources. United
States investors are advised that while such terms are
recognized and required by Canadian regulations, the United States Securities and Exchange
Commission does not recognize them. "Inferred" mineral resources
have a great amount of uncertainty as to their existence, and as to
their 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 other
economic studies except in limited circumstances and with specific
notification to the reader. United
States investors are cautioned not to assume that all or any
part of any mineral resources will ever be converted into mineral
Reserves (as defined under NI 43-101). United States investors are also cautioned not
to assume that all or any part of an Inferred mineral resource
exists, or is economically or legally mineable.
SOURCE Great Western Minerals Group Ltd.