VANCOUVER, Feb. 20, 2013 /PRNewswire/ - Commerce
Resources Corp. (TSXv: CCE, FSE: D7H, OTCQX: CMRZF) (the
"Company" or "Commerce") is pleased to announce additional results
from the on-going metallurgical programs on the Company's
100%-owned Ashram Rare Earth Element (REE) Deposit. Significant
metallurgical advancements have been made since those detailed in
the Company's News Release dated November
15th, 2012.
Highlights
- Production of reproducible, high-grade, rare earth mineral
concentrates with greater than 30.0% TREO
- Successful application of wet high intensity magnetic
separation (WHIMS) to mineral concentrate upgrading
- Significant advancement in sulphation roast-leaching
('cracking') of mineral concentrates using a two-acid method
Using conventional beneficiation and flotation
techniques, multiple mineral concentrates of greater than 30% Total
Rare Earth Oxide (TREO) have been produced including 40.0% TREO at
51.9% recovery, 30.7% TREO at 51.9% recovery, and 38.2% TREO at
44.8% recovery. These results represent TREO upgrading of
over 15 times the original grade into less than 5% of the original
mass (i.e. a mass reduction of more than 95%). In
addition, mineral concentrate grades of 18.2% TREO at 73.0%
recovery and 27.2% TREO at 58.4% recovery have been produced.
This demonstrates that high-grade mineral concentrates with higher
recoveries are achievable.
The high-grade mineral concentrates result from
the Ashram Deposit's simple rare earth mineralogy consisting of
monazite, bastnaesite, and xenotime. These three minerals
contain among the highest REO (>60%) contents of any known
mineral, dominate current commercial processing, and share common
and conventional processing techniques.
Company President David
Hodge states "We are excited by the considerable increase
in mineral concentrate grades and recoveries over the past 3-4
months. The REE mineral concentrates produced from Ashram
appear to be the highest grade of any developing rare earth
project. Our ability to create a high-grade mineral
concentrate will lead to reduced downstream processing costs and
acid consumption. This will have a positive and direct impact
on the Ashram Project's OPEX."
Physical Upgrade
To date, two successful approaches to physical
upgrading have been developed involving conventional flotation at
ambient temperatures, and wet high-intensity magnetic separation
(WHIMS). The final Ashram flowsheet will merge the best
attributes of both methods to develop an optimized approach of
physical upgrading to a high-grade rare earth mineral
concentrate. The production of a mineral concentrate is the
final step before undergoing a sulphation roast-leach ('cracking')
to liberate the REEs into solution.
Flotation (UVR-FIA GmbH)
The first method of physical upgrading is a size
fraction approach in which all the mineralized whole rock material
is ground and separated, via hydrocycloning and screening, into
three size fractions termed 'fine', 'middle', and 'coarse'. The
fine and middle size fractions are treated separately using
conventional flotation techniques optimized for that fraction,
while the coarse fraction is reground and classified proportionally
into the other two fractions. After each fraction has been
optimally upgraded they are recombined into a final high-grade
mineral concentrate.
This method has been the focus of UVR-FIA GmbH
of Freiberg, Germany under the direction of Gerhard Merker, a leading expert in mineral
flotation. Representative test results are listed in Table
1.
Table 1: Test Results of Flotation
Upgrading Using a Three Size Fraction Approach
Analytical
Method(1) |
Size
Fraction(s)(2) |
Test
ID |
Upgrading
Process |
% of
Original
Feed Weight |
Analysis
(TREO)(3) |
Recovery(4) |
Upgrade
Ratio(5) |
Grade and Recovery referenced to Size Fraction Input - fine,
middle, and coarse |
XRF |
Fine |
55-25/124 |
Flotation |
14.2% |
8.3% |
60.5% |
4.3 times |
XRF |
Middle |
58-18a |
Flotation |
10.0% |
22.4% |
88.4% |
11.5 times |
ICP |
Middle |
58-18b |
Flotation |
7.9% |
26.8% |
83.7% |
13.7 times |
XRF |
Fine(7) + Middle |
58-20a |
Flotation |
6.0% |
27.2% |
74.5% |
13.9 times |
ICP |
Middle |
58-13 |
Flotation |
5.4% |
29.7% |
70.1% |
15.2 times |
XRF |
Middle |
58-17a |
Flotation |
7.6% |
30.7% |
79.8% |
15.7 times |
ICP |
Middle |
58-16 |
Flotation |
5.3% |
32.9% |
72.9% |
16.9 times |
ICP |
Middle |
58-17b |
Flotation |
5.3% |
38.2% |
68.9% |
19.6 times |
XRF |
Fine(7) +
Middle |
58-20b |
Flotation |
4.1% |
40.0% |
66.5% |
20.5 times |
XRF |
Middle |
55-25-132 |
Flotation |
1.9% |
43.3% |
33.8% |
22.2 times |
- |
Coarse |
Re-ground proportionally back to fine and middle fractions |
Grade and Recovery referenced to Whole Rock
Input(6) |
XRF |
Fine + Middle +
Coarse |
55-25/124 + 58-18a |
Flotation |
11.7% |
15.5% |
78.6% |
7.9 times |
XRF/ICP |
Fine + Middle
+
Coarse |
55-25/124 + 58-18b |
Flotation |
10.4% |
16.7% |
75.6% |
8.6 times |
XRF |
Fine + Middle +
Coarse |
55-25/124 + 58-17a |
Flotation |
10.2% |
18.2% |
73.0% |
9.3 times |
XRF/ICP |
Fine + Middle +
Coarse |
55-25/124 + 58-17b |
Flotation |
8.8% |
19.0% |
66.0% |
9.7 times |
XRF |
Fine(7) + Middle
+
Coarse |
58-20a |
Flotation |
4.2% |
27.2% |
58.4% |
13.9 times |
XRF |
Middle +
Coarse
(Fine Discarded) |
58-17a |
Flotation |
4.5% |
30.7% |
51.9% |
15.7 times |
ICP |
Middle +
Coarse
(Fine Discarded) |
58-16 |
Flotation |
3.2% |
32.9% |
47.4% |
16.9 times |
ICP |
Middle +
Coarse
(Fine Discarded) |
58-17b |
Flotation |
3.2% |
38.2% |
44.8% |
19.6 times |
XRF |
Fine(7) + Middle +
Coarse |
58-20b |
Flotation |
2.9% |
40.0% |
51.9% |
20.5 times |
(1) |
XRF refers to quantitative analysis by XRF using a fusion
bead/tablet. XRF analysis is typically completed for Ce and
La only with TREO extrapolated based on the correlation factor
noted below. ICP analysis is quantitative with TREO defined
as Ce2O3 + La2O3 +
Pr2O3 + Nd2O3 +
Eu2O3 + Sm2O3 +
Gd2O3 + Tb2O3 +
Dy2O3 + Ho2O3 +
Er2O3 + Tm2O3 +
Yb2O3 + Lu2O3 +
Y2O3. |
(2) |
The fine, middle, and coarse fractions comprise 28%, 53%, and
19% of the total whole rock REE content respectively.
Assuming the proportional re-grind of the coarse fraction into the
fine and middle fractions, the fine and middle fractions would
comprise 35% and 65% of the total REE content respectively. |
(3) |
ICP provides a quantitative value for TREO. XRF TREO is
calculated from Ce (metal) using a correlation factor as determined
from multiple ICP analysis. |
(4) |
Recovery is based on Ce and is assumed to be constant over all
the REEs as is indicated from prior testing. |
(5) |
Based on an average 1.95% TREO starting head grade. |
(6) |
Assumes coarse fraction undergoes a proportional regrind into
the fine and middle fractions. |
(7) |
Test 58-20 uses a modified size classification approach where a
portion of the fine fraction is further separated. The
coarsest fine fraction is then added to the middle fraction for a
total whole rock REE content of 78% as opposed to the 65% as
outlined in footnote (2) above. |
The most significant upgrading occurs in the
middle fraction where reproducible mineral concentrates of 20% to
40% TREO at 65% to 88% recovery have been achieved. Upgrading
in the fine fraction has achieved 8+% TREO mineral concentrates at
60+% recoveries, although work completed to date has not been as
extensive as with other size fractions. Test work, including lock
cycle tests, is ongoing to confirm the regrind and proportional
classification of the coarse fraction and further optimize the
upgrading of each fraction. Preliminary test work suggests
that a higher proportion (up to 83% from the initial 65%) of the
reground coarse fraction reports to the middle fraction.
In addition to producing high-grade mineral
concentrates, a key benefit of this method is the reduced fluorite
content in the mineral concentrates compared to those previously
produced. This will significantly reduce the amount of
calcium (Ca) and fluorine (F) present during the sulphation
roast-leach process that follows, and is expected to allow for
improved overall recoveries.
Flotation + WHIMS (Hazen Research
Inc.)
The second method of physical upgrading is being
developed at Hazen Research Inc. of Colorado, USA and involves the use of
conventional flotation followed by wet high intensity magnetic
separation (WHIMS). The method treats the whole rock material
directly by flotation before undergoing WHIMS, rather than using a
sizing approach.
Using this method of flotation, mineral
concentrates of 10-15% TREO at 69-83% recovery have been created
with good reproducibility and minimal optimization, leaving good
potential for additional upgrading. Producing these
concentrates has resulted in a significant mass reduction of 84-91%
of the material to be processed downstream. Representative
results are listed in Table 2
Table 2: Test Results of Flotation Upgrading Without
Sizing (Whole Rock)
Analytical
Method(1) |
Test ID |
Upgrading
Process |
% of
Original
Feed Weight |
Analysis
(TREO)(1) |
Recovery(2) |
Upgrade
Ratio(3) |
ICP |
3638-1 |
Flotation
(Cleaner 1 of 2 Roughers) |
9.1% |
15.0% |
68.9% |
7.7 times |
ICP |
3612-155 |
Flotation |
11.2% |
13.4% |
75.0% |
6.9
times |
ICP |
3612-116 |
Flotation |
15.1% |
10.6% |
79.6% |
5.4 times |
ICP |
3638-1 |
Flotation
(Cleaner 1 of 4 Roughers)(4) |
16.3% |
10.1% |
82.9% |
5.2 times |
(1) |
ICP analysis is quantitative with TREO defined as
Ce2O3 + La2O3 +
Pr2O3 + Nd2O3 +
Eu2O3 + Sm2O3 +
Gd2O3 + Tb2O3 +
Dy2O3 + Ho2O3 +
Er2O3 + Tm2O3 +
Yb2O3 and + Y2O3.
Lu2O3 is not included in the summation. |
(2) |
Recovery is based on ICP data of all available TREO. |
(3) |
Based on an average 1.95% TREO starting head grade. |
(4) |
Based on recycle of cleaner tails to preceding rougher
stage |
The WHIMS method uses the magnetic properties
inherent in each mineral to achieve separation. Flotation
produces a mineral concentrate consisting of fluorite
(diamagnetic), carbonate minerals (paramagnetic), and REE minerals
(paramagnetic). As such, the fluorite will preferentially
report to the non-magnetic fraction and the carbonate + REE
minerals to the magnetic fraction. The following figure
illustrates visually the upgrading as exemplified in test
3612-117.
Figure 1: WHIMS Products from Flotation
Concentrate (Test 3612-117)
(http://files.newswire.ca/1071/WHIMS_Image-01.jpg)
Table 3: Select Test Result of Mineral
Concentrate Upgrading via Conventional Flotation and WHIMS
|
Whole
Rock
Material |
REE
Mineral
Concentrate(1) |
WHIMS
(Magnetic Fraction)(1) |
WHIMS
Referenced to
Concentrate Feed |
Test ID |
- |
3638-10 |
3638-43 |
- |
Upgrading
Process |
None
(Original Feed) |
Flotation of
Whole
Rock Material |
Flotation
(3638-10) +
WHIMS |
- |
Weight |
989.1g |
163.0g |
124.2g |
- 38.8g |
% of Original
Feed Weight |
100% |
16.5% |
12.6% |
24% reduction
in weight |
TREO(2) Content |
2.0% |
9.7% |
11.8% |
22% increase
in grade |
TREO
Recovery(3) |
100% |
79.5% |
75.2% |
95%
recovery |
TREO Upgrade
Ratio |
0 times |
4.9 times |
5.9 times |
- |
|
|
|
|
|
Fluorite
Content(3) |
5.9% |
29.6% |
15.2% |
51% decrease in
fluorite grade |
Fluorite
Recovery |
100% |
82.3% |
31.9% |
61% fluorite
rejection |
|
|
|
|
|
(1) |
Results referenced to Whole Rock Material (original feed) |
(2) |
TREO determined by Portable XRF for the LREO
(Ce2O3, La2O3,
Pr2O3, and Nd2O3) with
extrapolation, based on known distribution, used to determine the
value for the remaining REOs. The extrapolation assumes
recovery remains constant across all the REOs. The Portable XRF
(semi-quantitative) vs. ICP (quantitative) analytical methods have
consistently shown to correlate well for
Ce2O3, La2O3,
Pr2O3, and Nd2O3 due to
the fine grain size and homogenous character of the mineral
concentrates, thereby allowing for a quick, economic, and effective
means of characterizing a mineral concentrate. |
(3) |
Fluorite is calculated from fluorine analysis by selective ion
electrode using a conversion factor of 2.055. Assumes all
fluorine is contained within fluorite. |
The use of the WHIMS method has several
significant attributes that make it an attractive option to pursue
because it:
- Allows for a significant increase in TREO grade (>20%) at
minimal loss of recovery (5%), as well as a considerable decrease
in mass (~25%) referenced to the mineral concentrate feed.
- Provides potential for a metallurgical grade fluorspar credit
without additional refining. (Alternatively, the fluorite
product may potentially be further upgraded by additional flotation
to a more valuable ceramic or acid-grade product).
- Significantly reduces fluorite in the flotation mineral
concentrate which will reduce the acid consumption and may
potentially allow further REE upgrading via additional
flotation.
Sulphation Roast-Leach Tests
('Cracking')
Testwork on mineral concentrates produced at
Hazen has continued to provide promising results. A two acid
approach using a dilute hydrochloric acid (HCl) pre-leach to
dissolve the carbonate gangue (waste) minerals, followed by a
sulphuric acid (H2SO4) attack to dissolve the
REE minerals, is being pursued. The method has shown promise
for reducing overall acid consumption from the gangue components
and may allow for improved REE recoveries into solution. For
example, in an initial test, dilute HCl solution at ambient
temperature was added to a flotation concentrate at a ratio of
520kg (100% HCl basis) per tonne of concentrate (~155kg per tonne
of whole rock ore) to dissolve the carbonate gangue. The test
resulted in the removal of ~70% of the concentrate's mass with only
3% REE loss while increasing the grade from ~3.8% to ~9.9% TREO (an
upgrade of 2.6 times)
This test was completed on a low grade mineral
concentrate (~3.8% TREO) and will be repeated on higher grade
concentrates (10-15+% TREO) in the near term. This will be
followed with sulphuric acid attack on the residues allowing for
more complete characterization of acid consumption and REE
recoveries into solution. The HCl consumption is a function
of the amount of carbonate and fluorite in the concentrate and is
expected to decrease for higher grade mineral concentrates
containing less of these gangue components.
The remaining mineral concentrate, containing
~9.9% TREO, consisting dominantly of rare earth and presumably
fluorite minerals, may be subjected to the WHIMS method a second
time. This would provide additional upgrading before
undergoing a sulphuric acid roast to decompose the rare earth
minerals. Previous sulphation roast-leach tests had focused
on a sulphuric acid roast with no hydrochloric acid pre-leach step,
and although these were successful, the two-acid approach offers a
much more efficient process. Further, caustic cracking (NaOH)
is also being evaluated as an alternative method of producing a
rare earth end-product because of the high-grade mineral
concentrates now being produced.
Darren L. Smith,
M.Sc., P.Geol., Dahrouge Geological Consulting Ltd., a Qualified
Person as defined by National Instrument 43-101, supervised the
preparation of the technical information in this news release.
Eric Larochelle, Eng, and Alain Dorval, Eng.,
Manager- Process, Mining and Mineral Processing., of Roche Ltd,
Consulting Group, Qualified Persons as defined by National
Instrument 43-101, reviewed the technical information presented in
this news release.
About Hazen Research Inc.
Hazen Research Inc., located in Colorado U.S.A, is an industry leader in
metallurgical processing including rare earths. Their
expertise extends across many commodities including base, precious,
and rare metals, as well as pilot plant level studies.
Over their 50+ year history, extensive
experience in the metallurgy of rare earths has been developed via
direct involvement on many rare earth projects having varying ore
and gangue mineralogy. They are therefore, very well-known to
industry, within and outside North
America, as a leader in mineral beneficiation and
hydrometallurgical processing of raw materials, including rare
earth mineralized material.
Hazen is the primary metallurgical facility
focused on defining the beneficiation and hydrometallurgical
flowsheet for the Ashram Deposit.
About UVR-FIA GmbH
UVR-FIA GmbH, located in Freiberg
Germany, is a mineral processing and research facility with
roots dating back to 1954. The surrounding region has a
history of over 800 years of mining and smelting with Freiberg
hosting the world oldest university of mining and metallurgy in the
world (Freiberg University of Mining and Technology, established in
1765).
R. Gerhard
Merker, a mineral processing engineer (Dipl.-Ing.) and
leading expert in flotation of carbonate and fluorite-bearing
bastnaesite ores, is consultant and manager of the Ashram Deposit's
test work at UVR. Mr. Merker has over 30 years'
experience in the raw material and recycling industry including
several years studying the Dong Pao Rare Earth Deposit in
Vietnam and other RE
deposits.
UVR-FIA is working in tandem with Hazen Research
to complete the Ashram Deposit`s flowsheet with a focus on fluorite
separation from the rare earth minerals.
About the Ashram Rare Earth Element
Deposit
The Ashram Rare Earth Element (REE) Deposit is a
carbonatite within the Eldor Property, located in north-eastern
Quebec. The Deposit has a measured
and indicated resource of 29.3 million tonnes at 1.90% TREO and an
inferred resource of 219.8 million tonnes at 1.88% TREO. The
deposit boasts a well-balanced distribution with enrichment in the
light, middle and heavy rare earth elements including all five of
the most critical elements (neodymium, europium, dysprosium,
terbium, and yttrium).
The REEs at Ashram occur in simple and
well-understood mineralogy, being primarily in the mineral monazite
and to a lesser extent in bastnaesite and xenotime. These minerals
dominate the currently known commercial extraction processes for
rare earths.
A Preliminary Economic Assessment, completed in
May of 2012 by SGS-Geostat of Montreal (Blainville) (see news release dated
May 24, 2012), outlines highly robust
economics for the Ashram Deposit. The PEA is based on a 4,000
tonne per day open-pit operation with an initial 25-year mine life
(300 years at economic cut-off if open-pit + underground
development), a pre-tax and pre-finance Net Present Value (NPV) of
$2.32 billion at a 10% discount rate,
a pre-tax/pre-finance Internal Rate of Return (IRR) of 44%, and a
pre-tax/pre-finance payback period of 2.25 years.
The company continues to advance the Ashram
Deposit with metallurgical programs at both UVR-FIA and Hazen
Research.
About Commerce Resources Corp.
Commerce Resources Corp. is an exploration and
development company with a particular focus on deposits of rare
metals and rare earth elements. The Company is focused on the
development of its Upper Fir Tantalum and Niobium Deposit in
British Columbia and the Ashram
Rare Earth Element Deposit in Quebec.
On Behalf of the Board of Director
COMMERCE RESOURCES CORP.
"David Hodge"
President and Director
Tel: 604.484.2700
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.
Forward-Looking Statements
This news release contains forward-looking information which are
subject to a variety of risks and uncertainties and other factors
that could cause actual events or results to differ from those
projected in the forward-looking statements. Forward looking
statements in this press release include the focus of the
metallurgical work, the results of the on-going metallurgical
programs the reported grades and potential cost reductions, that
the Ashram deposit can be developed economically as an open-pit
mine; all reference to and information contained in the
pre-feasibility study; and that we can build shareholder value
through the discovery and development of Canadian rare metal and
rare earth element deposits. These forward-looking statements are
based on the opinions and estimates of management and its
consultants at the date the information is disseminated. They are
subject to a variety of risks and uncertainties and other factors
that could cause actual events or results to differ materially from
those projected in the forward-looking information. Risks
that could change or prevent these statements from coming to
fruition include the ability to finance ongoing exploration,
development and metallurgical programs, changing costs for mining
and processing; changing forecasts of mine production rates; the
timing and content of upcoming work programs; geological
interpretations based on drilling that may change with more
detailed information; potential process methods and mineral
recoveries assumption based on test work; the availability of
labour, equipment and markets for the products produced; market
pricing for the products produced; and despite the current expected
viability of the project, conditions changing such that the
minerals on our property cannot be economically mined, or that the
required permits to build and operate the envisaged mine can be
obtained. The forward-looking information contained herein is given
as of the date hereof and the Company assumes no responsibility to
update or revise such information to reflect new events or
circumstances, except as required by law.
SOURCE Commerce Resources Corp.
Image with caption: "Figure 1: WHIMS Products from Flotation
Concentrate (Test 3612-117) (CNW Group/Commerce Resources Corp.)".
Image available at:
http://photos.newswire.ca/images/download/20130220_C6904_PHOTO_EN_23880.jpg