TIDMPREM
RNS Number : 3142I
Premier African Minerals Limited
16 June 2017
Premier African Minerals Limited / Ticker: PREM / Index: AIM /
Sector: Mining
For immediate release
16 June 2017
Premier African Minerals Limited
("Premier" or the "Company")
Excellent Metallurgical Testwork Results on Zulu
Premier African Minerals Limited, the AIM-traded,
multi-commodity resource and development Company focused on
Southern and Western Africa, is pleased to report excellent results
from the initial metallurgical test work study on its wholly-owned
Zulu Lithium and Tantalum project ("Zulu") in Zimbabwe. The test
work was completed by German based Dorfner Anzaplan GmbH
("Dorfner"), a leading authority in the field of lithium and
speciality minerals processing and treatment.
The Company will continue with additional test work to improve
the recoveries of lithium and associated minerals as well as
improve the flowsheet design and establishing capital and operating
costs for producing lithium from Zulu.
Highlights:
-- The best flotation test work on spodumene pegmatite achieved
an overall lithium recovery of 81.8% and a concentrate containing
6.5% Li O and 0.09% Fe(2) O(3) . This is well within the typical
range of spodumene concentrates for glass and ceramics as well as
feedstock for conversion to lithium carbonate
-- The best flotation test work on a mixed pegmatite sample
achieved a spodumene concentrate containing 5.9% Li O being
acceptable for spodumene concentrates as feed stock for lithium
carbonate production and a commercial grade petalite concentrate
containing 3.9% Li(2) O at exceptionally low Fe(2) O(3) content of
<0.01% at an overall recovery in the concentrates of an
estimated 70%
-- The tailings of spodumene and petalite flotation process
contain very low iron oxide concentrations in the range of 0.01%,
offering the potential for producing a high quality, low iron
feldspar and quartz as by-products (f) o(r) glass and ceramics
applications
-- Further metallurgical test work is planned including tests on
the recoveries of lithium bearing minerals, the recovery of a
saleable tantalite concentrates and high purity, low iron oxide
quartz and feldspar concentrates as well as optimise flowsheet
design.
-- Dorfner also recommend a test work programme for lithium
extraction to produce lithium carbonate and hydroxide to prove that
marketable lithium carbonate and hydroxide can be produced
George Roach, Chairman and CEO commented: "We are very excited
with these excellent initial metallurgical test work results. These
results demonstrate that we can produce a commercial grade, high
quality lithium mineral concentrates from both the spodumene and
petalite mineralisation at Zulu project. We will continue to
conduct further testing to optimise the recoveries and grades, as
well as improving the flowsheet design for the Zulu project."
The metallurgical test work results and the recently announced a
maiden Inferred Mineral Resource Estimate at Zulu of 20.1 million
tonnes grading 1.06% Li(2) O on only a part of the 3.5km strike
length of the Zulu project again confirm that the Zulu project has
all the hallmarks of a world-class lithium project."
Metallurgical Test Work
The test work was completed by German-based Dorfner Anzaplan
GmbH ("Dorfner"). Dorfner is a leading authority in the high purity
industrial and strategic minerals and metals businesses, providing
a multitude of services, such as materials testing and analysis,
industry expertise and market intelligence, basic and advanced
engineering services. For more information of Dorfner, please
visit: http://www.anzaplan.com/
The Executive Summary reproduced below has been extracted
without material adjustment or amendment from Dorfner's final
report on the Physical Processing of Lithium Pregmatite Ore from
the Zulu Pegmatite, Zimababwe dated 9 June 2017:
Executive Summary
Premier African Minerals, South Africa is in the process of
evaluating its Zulu Lithium Project in Zimbabwe developing a
beneficiation process for the lithium ore. The primary objective of
the present beneficiation test work was to develop a flow sheet for
lithium mineral concentration
including the following main items:
-- Sensor based sorting of lithium ore to separate dominantly petalite and spodumene ore
-- Process development on samples after sensor based sorting for spodumene and petalite mineral concentration
-- Laboratory heavy liquid separation (HLS), to evaluate the
amenability of the ore for dense media separation (DMS)
Three samples, labeled "Zulu Surface", "Zulu Adit", and "Zulu
Petalite" in the amount of 868 kg in total from the Zulu pegmatite
deposit were sampled by Premier African Minerals and sent to
Dorfner ANZAPLAN for processing tests. Sample "Zulu surface" is
strongly altered. It was therefore decided in consultation with
Premier African Minerals to not consider sample "Zulu surface" in
present test work. For the processing test work, a mixed sample of
"Zulu Adit" and "Zulu Petalite" was prepared
in a mixing ratio of 1:1 with a lithium oxide grade of the
combined sample of 1.1 wt.-%.
Sensor based sorting
Target of the sensor based sorting test work was to separate
spodumene rich ore from petalite rich ore as spodumene and petalite
require different flotation regimes.
For sorting the sample was crushed to -80 mm and screened into
fractions +3 -8 mm, +8 -25 mm, +25 mm for sorting and fines -3 mm.
A two stage optical sorting process was tested on the ore sample in
three size fractions (+3 -8 mm, +8 -25 mm, +25 mm). From each size
fraction, a spodumene rich fraction, intermediate product and a
petalite rich fraction was generated.
Based on the result of chemical and mineralogical analyses of
all fractions received after sensor based sorting, the following
two samples were combined for further processing tests:
-- A spodumene rich pre-concentrate containing no petalite
("spodumene ore sample") with a Li2O grade of 1.5 wt.-% containing
51 wt.-% of overall lithium oxide in 38 wt.-% of mass.
-- A "mixed ore sample" containing the intermediate product and
the petalite rich fraction with a Li2O grade of 0.9 wt.-%
containing 49 wt.-% of overall lithium oxide in 62 wt.-% of
mass.
Flotation test work
Mineral processing tests were carried out individually on the
two ore samples after sensor based sorting. The spodumene dominated
sample "spodumene ore sample" was subjected to spodumene flotation.
For the "mixed ore sample", spodumene and subsequently petalite
flotation was carried out as both minerals require different
flotation regimes.
In case of spodumene ore, the best results in terms of overall
recovery were calculated for test F4. A spodumene concentrate with
5.5 wt.-% Li2O in the rougher flotation concentrate at an overall
lithium recovery of 83.7 wt.-% was achieved. The rougher
concentrate was upgraded in one cleaner stage to a concentrate with
6.5 wt.-% Li2O at 81.8 wt.-% recovery in cleaner concentrate 1.
Additionally, only a low amount of lithium (1.9 wt.-%) is in the
cleaner tails, which are recirculated in the technical
process. Most of the lithium in the cleaner tails should also be
recoverable.
Thus an indicative estimate for overall lithium flotation
recovery is in the range of 83 wt.-% at a Li2O grade of 6.5wt.-%.
This has to be approved in locked cycle tests in future test work.
Definitive losses of lithium oxide are in slimes (4.3 wt.-%), mica
concentrate (8.1 wt.-%) and spodumene flotation tails (3.9 wt.-%),
which sum up to 16.3 wt.-%. In contrast to the spodumene ore
sample, the lithium grade in the mixed sample is significantly
lower (0.9 wt.-% after sorting). The mixed ore sample contains
about 5 wt.-% spodumene and 12 wt.-% petalite resulting in a
lithium distribution of approx. 60 wt.-% Li2O in petalite and 40
wt.-% in spodumene In the case of the mixed ore sample, the best
results in terms of overall recovery at grades in the range of
typical products were achieved in flotation test F15. There, 35.1
wt.-% of the lithium contained in the sample was recovered in the
spodumene cleaner concentrate at a grade of 5.8 wt.-% Li2O in 6.5
wt.-% of the mass. In addition, 17.4 wt.-% of the
lithium contained in the sample was recovered in the subsequent
petalite cleaner concentrate at a grade of 3.9 wt.-% Li2O in 4.8
wt.-% of the mass.
In this test a relatively high amount of the lithium reports to
the cleaner tails (in total 28.6 wt.-%) deriving mainly from
petalite flotation (21.3 wt.- %) as well as a minor quantity from
spodumene flotation (7.3 wt.-%). These cleaner tailings are
recirculated in the technical process. This implies that most of
the lithium in these cleaner tails should also be recoverable.
However, overall lithium recovery of the mixed ore sample in
continuous process is assumed lower, and is estimated to be in a
range of
about 70 wt.-%. Again, this has to be approved in locked cycle
flotation tests in future test work.
Definitive losses of lithium are observed in the best test for
the mixed ore sample in the slimes (4.5 wt.-%), mica concentrate (8
wt.-%) and petalite tails (6.4 wt.-%). Minor additional losses of
lithium are in the cleaner tails 5 (0.9 wt.-%), which have to be
removed from the process to separate quartz and cannot be
recirculated. Therewith definitive losses sum up to 19.8 wt.-% for
the mixed ore sample.
Mineral concentrates
Best results in spodumene concentrate quality were achieved with
the spodumene ore sample in test F4. There a spodumene concentrate
at 6.5 wt.-% Li2O and an iron oxide concentration of 0.09 wt.-%
was
achieved, being well within the typical range of spodumene
concentrates for glass and ceramics as well as feedstock for
conversion to lithium carbonate. In the case of a mixed ore sample
a spodumene concentrate grading 5.9 wt.-% Li2O was obtained at an
iron oxide content in the range of 0.6 wt.-% being acceptable for
spodumene as feed stock for lithium carbonate production.
Introducing an additional magnetic separation step an iron oxide
content of 0.16 wt.-% was achieved, being only slightly elevated
compared to typical standard glass grade spodumene products. The
best petalite concentrate was generated in test F15 resulting in a
Li2O grade of 3.9 wt.-% being in the range of typical petalite
concentrate grades of 4 wt.-% Li2O content. The benefit of petalite
from the Zulu
deposit is the exceptionally low iron oxide content. In the best
petalite concentrate an iron oxide value of <0.01 wt.-% compared
to 0.04 wt.-% in typical products was analyzed being beneficial
with respect to glass and ceramics application.
Recommended flow sheet
Based on test work results a flow sheet is recommended
comprising the following main processing steps:
-- Based on HLS test results it appears feasible that using DMS
it is possible to produce a spodumene enriched heavy fraction
containing only spodumene besides quartz, feldspar and other non
lithium bearing silicates. The light fraction from DMS represents
the mixed ore fraction being enriched in lithium minerals, mainly
petalite and some residual spodumene. In addition a middle
fraction, depleted in lithium, can be rejected for mass reduction
prior to flotation. However, this has to be confirmed in pilot DMS
tests.
-- Separate processing of spodumene and mixed ore after DMS is
suggested to be processed in the same plant, however with
alternating feed. This offers the advantage that the spodumene ore
has to be treated only up to spodumene flotation.
-- The ore sample is crushed and ground to target grind size
(150 <MU>m) and then deslimed by hydro cyclone. The deslimed
ore is used as feed material for flotation.
-- Magnetic separation of mixed ore in case low iron glass grade
spodumene is targeted to be produced.
-- Mica flotation to provide purified feed material for
subsequent spodumene flotation, being necessary to achieve high
grade spodumene concentrates.
-- Spodumene flotation to produce a high grade spodumene concentrate.
-- In case of mixed ore: Further processing of spodumene
flotation tailings to produce a petalite concentrate.
Recommendations
Based on the results of present test work, the following
recommendations are made for future metallurgical testing to
develop the lithium project:
-- Dense media separation test work for pre-concentration and
separation into spodumene and petalite enriched fractions.
-- Flotation tests on samples from DMS are recommended
especially for petalite flotation to investigate potential
improvements (improved petalite grade and simplification of
petalite flotation process)
-- Conduct locked cycle test work for spodumene and petalite
flotation to confirm overall flotation recoveries and the influence
on concentrate grade and recovery when recirculating cleaner
tailings.
-- It is recommended to investigate the lithium mineral
distribution within the deposit, to evaluate if petalite and
spodumene ore can be mined selectively.
-- In tailings of spodumene and petalite flotation respectively
very low iron oxide concentrations in the range of 0.01 wt.-% were
analyzed. Production of high quality, low iron feldspar and quartz
by-products
-- for glass and ceramics applications appear feasible. It is
recommended to investigate if there is a local market for such
products in Zimbabwe or surrounding countries. If this is the case
test work to produce quartz and feldspar by-products is
recommended.
-- A test work program for lithium extraction to produce lithium
carbonate and hydroxide is recommended to prove that marketable
lithium carbonate and hydroxide can be produced from spodumene
respectively petalite concentrates from the Zulu deposit.
-- An ore variability study is recommended to investigate the
impact of varying feed composition on grade and recovery of
flotation.
-- Finally an economic evaluation of the project in a scoping
study or preliminary economic assessment (PEA) is recommended to
further develop the Zulu lithium project.
Glossary of Technical Terms:
Fe(2) O(3) is the chemical formula of iron oxide
Flotation is a process for selectively separating
hydrophobic materials from hydrophilic.
This is used in mineral processing,
paper recycling and waste-water treatment
industries
"Inferred that part of a Mineral Resource for
Resource" which tonnage, grade and mineral content
can be estimated with a low level
of confidence. It is inferred from
geological evidence and sampling and
assumed but not verified geological
and/or grade continuity. It is based
on information gathered through appropriate
techniques from locations such as
outcrops, trenches, pits, workings
and drill holes that may be limited
or of uncertain quality and reliability
"K-feldspar" is a general term for potassium bearing
feldspars KAlSi(3) O(8) , a common
rock forming mineral
"Lepidolite" is the mineral name for lithium bearing
mica KLi(2) Al(Si(4) O(10) )(F,OH)(2)
an important ore of lithium
"Li(2) O" chemical formula of lithium oxide
"Lithium Carbonate is the industry standard terminology
Equivalent for, and is equivalent to, Li(2) CO(3)
(LCE)"
"Measured that part of a mineral resource for
mineral resource" which quantity, grade or quality,
densities, shape, and physical characteristics
are so well established that they
can be estimated with confidence sufficient
to allow the appropriate application
of technical and economic parameters,
to support production planning and
evaluation of the economic viability
of the deposit. The estimate is based
on detailed and reliable exploration,
sampling and testing information gathered
through appropriate techniques from
locations such as outcrops, trenches,
pits, workings and drill holes that
are spaced closely enough to confirm
both geological and grade continuity
"Mica" is a general term for a group of sheet
silicate minerals, it includes several
closely related minerals having nearly
perfect basal cleavage, KAl(2) (Si(3)
Al)O(10) (OH,F)(2) ; micas are common
rock forming minerals.
"Mineral resource" concentration or occurrence of diamonds,
natural solid inorganic material or
natural fossilized organic material
including base and precious metals,
coal, and industrial minerals in or
on the Earth's crust in such form
and quantity and of such a grade or
quality that it has reasonable prospects
for economic extraction. The location,
quantity, grade, geological characteristics
and continuity of a mineral resource
are known, estimated or interpreted
from specific geological evidence
and knowledge.
"Pegmatite" an exceptionally coarse-grained igneous
rock, with interlocking crystals,
usually found as irregular dikes,
lenses, or veins, esp. at the margins
of granitic intrusions
"Petalite" the mineral name for lithium aluminium
silicate LiAl(Si(4) O(10) ) an important
ore of lithium.
"ppm" means parts per million
"Quartz" one of the most common rock forming
minerals with the chemical composition
SiO2 (silicon dioxide)
"Spodumene" the mineral name for lithium aluminium
silicate LiAlSi(2) O(6) an important
ore of lithium.
"Ta(2) O(5) chemical formula of ditantalum pentoxide
"
"Tantalum is the inorganic compound with the
pentoxide" formula Ta(2) O(5) ,
"Tantalite" a mostly dark grey to black mineral,
manganese bearing varieties are called
manganotantalite or tantalite-(Mn)
MnTa(2) O(6) ; a major tantalum ore.
wt.-% is weight percent
Forward Looking Statements:
Certain statements in this announcement, are, or may be deemed
to be, forward looking statements. Forward looking statements are
identi ed by their use of terms and phrases such as "believe",
"could", "should" "envisage", "estimate", "intend", "may", "plan",
"will" or the negative of those, variations or comparable
expressions, including references to assumptions. These
forward-looking statements are not based on historical facts but
rather on the Directors' current expectations and assumptions
regarding the Company's future growth, results of operations,
performance, future capital and other expenditures (including the
amount, nature and sources of funding thereof), competitive
advantages, business prospects and opportunities. Such forward
looking statements re ect the Directors' current beliefs and
assumptions and are based on information currently available to the
Directors. A number of factors could cause actual results to differ
materially from the results discussed in the forward-looking
statements including risks associated with vulnerability to general
economic and business conditions, competition, environmental and
other regulatory changes, actions by governmental authorities, the
availability of capital markets, reliance on key personnel,
uninsured and underinsured losses and other factors, many of which
are beyond the control of the Company. Although any forward-looking
statements contained in this announcement are based upon what the
Directors believe to be reasonable assumptions, the Company cannot
assure investors that actual results will be consistent with such
forward looking statements.
Competent Persons Statement:
The information in this announcement that relates to the Mineral
Resource Estimate is based on data compiled and verified by
Wolfgang Hampel. Wolfgang Hampel, Exploration Manager of Premier
African Minerals Limited has reviewed and approved this release to
the extent that reference is made to the Zulu tenements. Mr Hampel
has 26 years' relevant experience in the African, American,
European and Asian exploration and mining industry and holds a
Diploma in Economic Geology (Dipl.-Geol.) from the Technical
University of Munich. He is a registered European Geologist
(EurGeol), ndeg 1261, with the European Federation of Geologists.
Mr Hampel has sufficient experience which is relevant to the style
of mineralisation and types of deposits under consideration, and to
the activity which has been undertaken, to qualify as a Competent
Person as defined by the 2007 edition of the South African Code for
Reporting of Exploration Results, Mineral Resources and Mineral
Reserves (SAMREC). Mr Hampel has reviewed and approved this
announcement and the commentary above to the extent reference is
made to geological resource and resource grade and accepts
responsibility for the accuracy of these statements disclosed in
this announcement.
This announcement contains inside information for the purposes
of Article 7 of EU Regulation 596/2014.
Enquiries:
Premier African Minerals Tel: +44 (0)7734
Fuad Sillem Limited 922074
------------------ --------------------------- ------------------
Michael Cornish Beaumont Cornish Tel: +44 (0) 207
/ Roland Cornish Limited 628 3396
(Nominated Adviser)
------------------ --------------------------- ------------------
Jerry Keen/Edward Shore Capital Stockbrokers Tel: +44 (0) 207
Mansfield Limited 408 4090
------------------ --------------------------- ------------------
Beaufort Securities Tel: +44 (0) 20
Jon Belliss Limited 7382 8300
------------------ --------------------------- ------------------
Charles Goodwin/ Yellow Jersey PR Tel: +44 (0) 7747
Harriet Jackson Limited 788221
------------------ --------------------------- ------------------
Notes to Editors:
Premier African Minerals Limited (AIM: PREM) is a
multi-commodity mining and natural resource development company
focused in Southern and Western Africa with production started at
its flagship RHA project in Zimbabwe.
The Company has a diverse portfolio of projects, which include
tungsten, rare earth elements, gold, lithium and tantalum in
Zimbabwe and Benin, encompassing brownfield projects with near-term
production potential to grass-roots exploration. The Company
recently acquired a 52% controlling stake in Mozambique-based TCT
Industrias Florestais Limitada, which owns a substantial limestone
deposit and forestry business located on rail in the Sofala
Province of Mozambique. In addition, the Company holds 2 million
shares in Circum Minerals Limited ("Circum"), the owners of the
Danakil Potash Project in Ethiopia, which has the potential to be a
world class asset. At present those shares are valued at US$4
million based on the latest price at which Circum has accepted
subscriptions. Premier also has an interest in Casa Mining Limited,
a privately-owned exploration company that has a 71.25% interest in
the 1.2 million ounce inferred resource Akyanga gold deposit in the
DRC.
ENDS
This information is provided by RNS
The company news service from the London Stock Exchange
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