Macarthur Minerals Substantially Increases its Hematite Resource Inventory, Supported by Metallurgical Testwork
14 Juni 2012 - 3:30PM
Marketwired Canada
THIS NEWS RELEASE IS NOT FOR DISTRIBUTION TO UNITED STATES SERVICES OR FOR
DISSEMINATION IN THE UNITED STATES.
Macarthur Minerals Limited (TSX:MMS)(OTCQX:MMSDF) (the "Company" or "Macarthur")
is pleased to announce a substantial increase in the hematite/goethite Mineral
Resource inventory at the Ularring Hematite Project.
Highlights
-- Results of two metallurgical test work programs indicate that it is
technically possible to beneficiate lower grade hematite/goethite
material and thereby reduce the cut-off grade.
-- Indicated Mineral Resource inventory has increased from a total of 13.01
Mt @ 55.2% Fe(1) at a cut-off grade of 50% Fe to 54.46Mt @ 47.2% Fe at a
cut-off grade of 40% Fe.
-- Inferred Mineral Resource inventory has increased from a total of 16.95
Mt @ 55.6% Fe(1)at a cut-off grade of 50% Fe to 25.39Mt @ 45.2% Fe at a
cut-off grade of 40% Fe (excluding 0.6Mt at Moonshine).
(1)Technical Report filed March 8, 2012
Macarthur's President, Chairman and CEO, Alan Phillips, commented that, "The
completion of the infill drilling campaign for conversion of Inferred Mineral
Resources to Indicated Mineral Resources coupled with the encouraging results of
metallurgical test work programs prompted Mineral Resource estimation based on
lower cut-off grades. The release of the new Mineral Resource estimate is a
further positive step towards demonstrating the potential of the Company's
hematite Mineral Resource. Macarthur has again exceeded its stated resource
goals and the Company is now moving rapidly ahead with project approvals for the
development of the Ularring Hematite Project."
Metallurgical Test Results
The previous Mineral Resource estimation used a 50% Fe cut-off grade to define
Mineral Resource volumes. Phase one metallurgical testing (News Release November
21, 2011) conducted in late 2011 indicated that it is technically possible to
recover material with a grade greater than 60% Fe with a recovery of over 63%
using conventional gravity beneficiation from comparatively high grade starting
materials. The results of the recently completed second phase of metallurgical
testing provided evidence for the process - ability of a range of material types
and grades and prompted re-evaluation of the Mineral Resource inventory at a 40%
Fe cut-off grade (News Release June 1, 2012).
Further Mineral Resource Definition
The current Mineral Resource estimate also incorporates all the results from the
Company's latest resource definition reverse circulation ("RC") drilling program
at its Snark, Drabble Downs, Banjo and Central deposits. The total number of
holes drilled in these deposits to date this calendar year was 290 holes for a
19,411 metre advance.
June 2012 Mineral Resource Estimation
Independent mining consultancy group CSA Global Pty Ltd ("CSA") was commissioned
by Macarthur to generate a new National Instrument 43-101 ("NI 43-101") Mineral
Resource estimate for the Ularring Hematite Project, presently comprised of five
separate deposits being Snark, Drabble Downs, Central, Banjo (previously called
Banjo-Lost World) and Moonshine.
The previous Mineral Resource estimate was based upon a nominal 50% Fe cut-off
grade. As a consequence of the positive metallurgical test work (News Release
June 1, 2012) which has demonstrated that the lower grade mineralisation in the
Ularring Hematite Project is amenable to beneficiation, Macarthur and CSA have
utilised a geological model which encapsulates the host Banded Iron Formation
("BIF") strata. The new Mineral Resource estimate has been constrained by the
BIF envelope and is reported from all blocks above a 40% Fe cut-off grade and
incorporates all of the drill results to date. The exception to this is the
Moonshine deposit's Mineral Resource, which was modelled using a 50% Fe envelope
and is reported for blocks greater than 50% Fe. This is discussed in the
Technical Report filed March 9, 2012.
Table 1. Ularring Hematite Project Mineral Resource at June 2012
----------------------------------------------------------------------------
Tonnes Fe P SiO2 Al2O3 LOI S
Category Mt % % % % % %
----------------------------------------------------------------------------
Indicated 54.46 47.2 0.06 16.9 6.5 7.9 0.16
----------------------------------------------------------------------------
Inferred 25.99 45.4 0.06 20.6 6.0 7.2 0.09
----------------------------------------------------------------------------
Note: The CSA mineral resource was estimated within constraining wireframe
solids encapsulating BIF strata. The resource is quoted from blocks above
40 Fe % cut-off grade, except Moonshine where resource is quoted from
blocks above 50 % Fe. Differences may occur due to rounding.
The previous published Mineral Resource for the Ularring Hematite Project is
presented in Table 2 (Technical Report filed March 9, 2012). The current Mineral
Resource is reported by deposit in Table 3.
Table 2. Ularring Hematite Project Mineral Resource published in January 2012
----------------------------------------------------------------------------
Tonnes Fe P SiO2 Al2O3 LOI S
Category Mt % % % % % %
----------------------------------------------------------------------------
Indicated 13.01 55.2 0.07 8.0 4.4 7.8 0.17
----------------------------------------------------------------------------
Inferred 16.95 55.6 0.07 8.1 4.4 7.4 0.15
----------------------------------------------------------------------------
Note: The CSA Mineral Resource (January 2012) was estimated within
constraining wireframe solids based on a nominal lower cut-off grade of 50%
Fe. The resource is quoted from blocks above 50Fe % cut-off grade.
Differences may occur due to rounding.
Table 3. June 2012 Ularring Hematite Project Mineral Resource by Deposit
----------------------------------------------------------------------------
Reporting
cut-off
grade Tonnes Fe P SiO2 Al2O3 LOI S
Deposit (Fe%) Category Mt % % % % % %
----------------------------------------------------------------------------
Snark 40 Indicated 21.83 47.2 0.07 17.5 6.1 7.7 0.15
------------------------------------------------------------------
40 Inferred 10.96 45.2 0.07 21.8 5.1 6.8 0.09
----------------------------------------------------------------------------
Drabble 40 Indicated 11.07 47.2 0.06 16.6 6.4 8.3 0.26
------------------------------------------------------------------
Downs 40 Inferred 0.36 43.6 0.05 24.0 4.8 7.8 0.09
----------------------------------------------------------------------------
Central 40 Indicated 15.09 47.0 0.05 16.2 7.2 8.1 0.12
------------------------------------------------------------------
40 Inferred 10.19 45.3 0.06 20.3 6.3 7.5 0.08
----------------------------------------------------------------------------
Banjo 40 Indicated 6.47 47.8 0.06 16.7 6.6 7.4 0.14
------------------------------------------------------------------
40 Inferred 3.88 45.4 0.06 18.7 7.6 7.9 0.09
----------------------------------------------------------------------------
Moonshine 50 Inferred 0.60 53.0 0.06 13.4 6.7 6.1 0.15
----------------------------------------------------------------------------
The Mineral Resource estimate completed by CSA for all deposits is based on the
following:
-- Macarthur supplied geological and sampling data and geological support
to CSA during the mineral resource modelling process.
-- Macarthur interpreted the BIF strata and supplied CSA with 3-D solid
wireframes encapsulating the BIF.
-- CSA prepared a validated drill hole database to support the current
Mineral Resource estimate.
-- CSA carried out grade estimation and Mineral Resource reporting using
Datamine software.
-- Density data was collected by downhole geophysical probe, which measured
the width of the hole and the corresponding density of the wall rock.
These results were correlated with the corresponding sample assay (Fe
%), and an algorithm delineated to calculate block density according to
estimated iron grade.
-- No diamond drill core was sampled and therefore not used in the grade
interpolation. The RC holes are sampled at 1m intervals.
-- No top cuts were applied to any grade variable.
-- Variograms were modelled for Fe and P. The variograms gave reasonable
structures along strike but poorly defined structures with limited rages
in the down dip direction.
-- Three Datamine block models were constructed for each of the deposits,
with blocks based on the modelled wireframed BIF zones. The models used
a parent cell size of 10m x 25m x 10m (X x Y x Z) with subcells down to
1.0m x 2.5m x 1.0m to model the steeply dipping narrow lenses.
-- Ordinary Kriging ("OK") was used to estimate the grades into the parent
blocks for Fe, P, SiO2, Al2O3, S and LOI.
-- Search radii were 100 m along strike, 100 m across strike and 15 m
vertically. Each BIF domain was estimated individually, using only those
samples located within the individual domains. The large radii width
across strike did therefore not source sample data from adjacent
domains. The limited vertical radii were used to control the vertical
spread of grade, in order to prevent known mineralisation into the low
grade (Fe %) BIF and vice versa.
-- A minimum of 8 samples and a maximum of 24 samples were used to estimate
the sample grades into each block for the first search pass. The minimum
number of samples was reduced to 2 for the third search pass.
-- A maximum of 5 samples from any one drill hole were used per block
estimate, with cell discretisation of 3 x 3 x 3 (X x Y x Z). Octant
based searching was not used.
-- The results of the grade estimation were validated by means of visual
comparison along sections, statistical analysis and trend plots
comparing the estimated block grades and the drill hole sampling grades.
-- A light detection and ranging ("LIDAR") topographic survey was flown in
June 2011 and the data derived from this was re-sampled to 2 m contours.
A digital terrain model ("DTM") was produced and used in the Mineral
Resource estimate.
-- The Mineral Resource was classified as Indicated and Inferred according
to the reporting guidelines of NI 43-101. The classification is based
upon an assessment of the drill sample data at time of publication,
using long section plots of each domain to determine Indicated
classification perimeters. The geological interpretation was guided by
surface fact mapping of hematite / BIF ridges. Indicated classification
generally extended from surface to a depth of between 30 m and 60 m
below surface. Each mineralisation domain was classified independently,
with some domains being set wholly to Inferred due to limited drill hole
support. A minimum of 5 drill holes per domain was required for a domain
to be considered for Indicated classification. Deep seated blocks were
not classified where there was no drill hole support at those depths to
support the geological interpretation and grade estimation. The
classification level is based upon an assessment of geological and
mineralisation continually, quality control results and an analysis of
available density information.
-- The Moonshine hematite resource was not remodelled and is reported
herein at a 50% Fe grade cut-off, as discussed in the Technical Report
filed March 9, 2012.
-- Intersections reported have been verified by the Company's quality
assurance and quality control protocols. All samples collected from
drill holes were prepared by independent laboratories, Ultra Trace and
ALS Laboratories in Perth, WA and pulverised to 90% passing 75 microns
and then analysed for the iron suite using XRF.
Moving Forward
A significant proportion of the Company's tenements remain to be explored. The
Company is moving ahead to follow-up the results of regional airborne
geophysical surveys with geological mapping and ground magnetic surveys with a
view to identifying additional hematite/goethite mineralisation exploration
targets in new areas and prioritising such additional targets for drill testing
to further increase the Company's hematite/goethite resource inventory.
Several previously unmapped and undrilled areas of strong hematite/goethite
mineralisation have already been identified east of the Banjo deposit and south
of Cody's Ridge. This mineralisation has been observed from surface expressions
to occur over several kilometres of strike.
There are no known material legal, political, environmental or other risks that
could affect the potential development of the resources. Non-material risks the
Company has identified are set out in the Management Discussion and Analysis
that was filed on February 9, 2012. A NI 43-101 Technical Report for the project
will be lodged with SEDAR within the required time.
QUALIFIED PERSONS
The information in this release that relates to in-situ Mineral Resources is
based on information compiled by Mr David Williams, BSc (Hons), of CSA Global.
Mr Williams takes overall responsibility for the Mineral Resource. He is a
Member of the Australian Institute of Geoscientists and has sufficient
experience, which is relevant to the style of mineralisation and type of deposit
under consideration, and to the activity he is undertaking, to qualify as an
Independent Qualified Person within the meaning of NI 43-101. Mr Williams
consents to the inclusion of such information in this news release in the form
and context in which it appears.
Mr David Larsen, BSc (Geology), a member of the Australian Institute of
Geoscientists, is a full-time employee of Macarthur and is a Qualified Person as
defined in NI 43-101. Mr Larsen is in charge of Macarthur's exploration programs
and has reviewed and approved the technical information contained in this news
release.
Both Mr Williams and Mr Larsen are satisfied that the processes used are
standard industry operating procedures and methodologies. They have verified the
results and data disclosed in this release, including sampling, analytical, and
test data underlying the information or opinions contained in the release.
ABOUT MACARTHUR MINERALS LIMITED (TSX:MMS)(OTCQX:MMSDF)
Macarthur Minerals Limited is an Australian-based resource development company
currently focused on developing its Ularring Hematite Project, located in the
Yilgarn iron ore district in Western Australia. The Ularring Hematite Project is
located 110 km from rail infrastructure with a direct connection to the iron ore
exporting Port of Esperance, Western Australia.
In addition to the Ularring Hematite Project, Macarthur's Moonshine Magnetite
Project has an inferred resource of 1.3 Bt at 30.1% Fe (press release dated
December 15, 2010; NI 43-101 Technical Report dated March 25, 2011).
Positive Preliminary Economic Assessments were released to the market on the
Ularring Hematite Project in November 2011 (press release dated November 21,
2011) and the Moonshine Magnetite Project in February 2011 (press release dated
February 7, 2011).
On behalf of the Board of Directors,
MACARTHUR MINERALS LIMITED
Alan Phillips, President, Chairman & CEO
Caution Regarding Forward-Looking Statements
Certain of the statements made and information contained in this press release
may constitute forward-looking information and forward-looking statements
(collectively, "forward-looking statements") within the meaning of applicable
securities laws. Such forward-looking statements include our belief as to the
extent and timing of exploration programs and various studies, the results of
the preliminary economic assessments of the Company, the potential tonnage,
grade and cut-off of deposits, mineral resource estimates, results of
beneficiation and the viability of the Company's Projects.
The forward-looking statements in this press release reflect the current
expectations, assumptions or beliefs of the Company based upon information
currently available to the Company. With respect to forward-looking statements
contained in this press release, assumptions have been made regarding, among
other things, the reliability of information prepared and/or published by third
parties that are referenced in this press release or was otherwise relied upon
by the Company in preparing this press release. Although the Company believes
the expectations expressed in such forward-looking statements are based on
reasonable assumptions, such statements are not guarantees of future performance
and no assurance can be given that these expectations will prove to be correct
as actual results or developments may differ materially from those projected in
the forward-looking statements. Factors that could cause actual results to
differ materially from those in forward-looking statements include unforeseen
technology changes that results in a reduction in iron or magnetite demand or
substitution by other metals or materials, the discovery of new large low cost
deposits of iron magnetite and the general level of global economic activity.
Readers are cautioned not to place undue reliance on forward-looking statements
due to the inherent uncertainty thereof. Such statements relate to future events
and expectations and, as such, involve known and unknown risks and
uncertainties. The forward-looking statements contained in this press release
are made as of the date of this press release and except as may otherwise be
required pursuant to applicable laws, the Company does not assume any obligation
to update or revise these forward-looking statements, whether as a result of new
information, future events or otherwise.
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