TIDMTHR
RNS Number : 2729B
Thor Mining PLC
29 January 2020
29 January 2020
THOR MINING PLC
MAIDEN RESOURCE ESTIMATES - BONYA TUNGSTEN AND COPPER
Thor Mining Plc ("Thor") (AIM, ASX: THR) and Arafura Resources
Limited ("Arafura") (ASX: ARU) are pleased to advise maiden mineral
resource estimates for the White Violet and Samarkand tungsten and
copper deposits at Bonya, adjacent to the Thor Mining Molyhil
tungsten and molybdenum project.
The project is held in joint venture between Arafura (60%) and
Thor (40%) with Thor acting as manager, and each party contributing
to the cost according to their equity holding.
Highlights:
-- White Violet;
-- Inferred Resources of 495,000 tonnes, grading 0.22% Tungsten
Trioxide (WO ) and 0.06% copper (Cu), containing 1,090 tonnes of WO
, and 300 tonnes Cu.
-- Samarkand;
-- Inferred Resources of 245,000 tonnes, grading 0.19% Tungsten
Trioxide (WO ) and 0.13 % copper (Cu), containing 465 tonnes of WO
, and 320 tonnes Cu.
-- Both deposits outcrop and remain open at depth, while
Samarkand, in particular, shows potential for strike extension to
the copper mineralisation.
-- Each deposit considered amenable to open cut extraction for
significant components of the resource.
-- Both deposits situated in close proximity to the Thor Mining
Molyhil tungsten and molybdenum project, and potentially therefore
within economic trucking distance.
These resources add to previously announced Inferred Resources
at Bonya Copper of 230,000 tonnes, grading 2.0% Cu, containing
4,600 tonnes Cu (ref Table B and announcement of 24 November
2018).
Mr Mick Billing, Executive Chairman, commented:
"These maiden resources are very significant when combined with
the mining inventory of the nearby proposed Molyhil
development."
"More work is required, to convert these inferred resources to,
at least, Indicated classification, along with other technical,
environmental, and social impact assessments, however we have taken
very good first steps."
The Bonya project hosts additional known tungsten and copper
deposits, and some high tenor copper strike extension at Samarkand.
These will be tested in due course, and we expect that they will
further contribute to the life and value of the greater Molyhil
project."
"A solid improvement in the tungsten price during the December
quarter is also a very positive sign."
Gavin Lockyer, Managing Director of Arafura Resources,
commented:
"We are pleased to deliver the project's first tungsten
resources at White Violet and Samarkand, and feel quietly confident
the JV can build further value over time through the discovery and
delineation of additional tungsten and/or copper resources."
Table A: Bonya Tungsten Mineral Resources (15 January 2020)
Oxidation Tonnes WO(3) Cu
% Tonnes % Tonnes
White Violet Inferred Oxide 25,000 0.41 90 0.16 40
Fresh 470,000 0.21 980 0.06 260
Sub Total 495,000 0.22 1,070 0.06 300
Samarkand Inferred Oxide 25,000 0.11 30 0.07 20
Fresh 220,000 0.20 430 0.13 290
Sub Total 245,000 0.19 460 0.13 310
Combined Inferred Oxide 50,000 0.26 120 0.14 60
Fresh 690,000 0.21 1,410 0.08 550
Total 740,000 0.21 1,530 0.09 610
-------------------------- ----------- -------- ----- ------- ----- -------
Notes:
-- 0.05% WO(3) cut-off grade.
-- Totals may differ from the addition of columns due to rounding.
Table B: Bonya Copper Mineral Resources (announced 26 November
2018)
Oxidation Tonnes Cu
% Tonnes
Inferred Oxide 25,000 1.0 200
Fresh 210,000 2.0 4,400
Total 230,000 2.0 4,600
----------------------- -------- ---- -------
Notes:
-- 0.2% Cu cut-off grade.
-- Totals may differ from the addition of columns due to rounding.
-- The Company is not aware of any information or data which
would materially affect this previously announced resource
estimate, and all assumptions and technical parameters relevant to
the estimate remain unchanged.
A link to the Thor Mining website showing a map of the Bonya
deposits and proximity to Molyhil may be accessed via:
https://www.thormining.com/sites/thormining/media/maps/15-001-1d-bonya-resources.jpg
Summary of Resource Estimate and Reporting Criteria (White
Violet and Samarkand)
Geology and geological interpretation
The White Violet and Samarkand deposits are located
approximately 350km ENE of Alice Springs and approximately 30km
east of Thor's 100% owned Molyhil deposit.
Mineralisation at White Violet and Samarkand is interpreted as
being hosted predominantly within metamorphic calc-silicate skarns
and sheared hornfels associated with mafic intrusives, granites and
pegmatites. The target deposits are analogous to the nearby Molyhil
tungsten and molybdenum deposit which also contains some
copper.
The tungsten mineralisation is predominantly scheelite and
copper is most often present as chalcopyrite.
Drilling techniques and hole spacing
The drill hole database used for the mineral resource estimate
(MRE) contains a total of 21 RC holes for 1,762.2m of drilling at
White Violet and 17 RC holes for 1,202m of drilling at
Samarkand.
The majority of holes have been drilled at angles of between 50
- 75deg and approximately perpendicular to the strike of the
mineralisation. Geological and assay data for all drill holes was
used in the geological interpretation and MRE.
Sampling and sub-sampling
Samples from RC drilling were collected over an average 1m
interval and submitted for assay. Barren zones were sampled as 4m
composites. RC samples were homogenised and subsampled by either
rotary or riffle splitting.
Sample analysis method
All samples were sent to Nagrom in Perth for preparation and
analysis. The samples were sorted and dried. Primary preparation
involved crushing the whole sample. The samples were split to
obtain a sub-fraction which was then pulverized to 80% passing
75um. For the April drilling, preliminary analysis was via mixed
four acid digest and then ICP-OES. Samples with initial tungsten
results >0.1% were then assayed via peroxide fusion and ICP-MS.
For the October and November drilling all samples were analysed via
peroxide fusion and ICP_MS. Internal laboratory QA uses CRM's,
blanks, splits and replicates. A limited number of field standards,
blanks and duplicates have all been applied in the QAQC
methodology. Sufficient accuracy and precision have been
established for the type of mineralisation encountered and is
appropriate for QAQC in the Resource Estimation.
Cut-off grades
The current MRE for the White Violet and Samarkand deposits have
been reported at a cut-off grade of 0.05% WO(3) . Top cuts were
applied as follows: White Violet, WO(3) - 1.5% Cu - 0.5%,
Samarkand, WO(3) - 1.45% Cu - 1.5%.
Estimation methodology
Mineralisation wireframes were generated in Micromine software
using drill hole data supplied by Thor. Resource data was flagged
with unique mineralisation domain codes as defined by the wireframe
and composited to 1m lengths.
At White Violet, grade continuity analysis was undertaken in
Micromine software for WO(3) and Cu for the mineralised domain and
variogram models were generated in all three directions. Parameters
were used in the block model estimation. A block model with a
parent block size of 8x4x8m with sub-blocks of 2 x 1 x 2m has been
used to adequately represent the mineralised volume, with sub
blocks estimated at the parent block scale.
At Samarkand, the data did not support the development of
meaningful variograms. Grade estimation for WO(3) and Cu was
completed using the Inverse Distance squared (ID2) technique. A
block model with a parent block size of 4x8x8m with sub-blocks of 1
x 2 x 2m has been used to adequately represent the mineralised
volume, with sub blocks estimated at the parent block scale.
Molybdenum (Mo) has not been estimated despite the fact that it
can be an element of interest when considering tungsten deposits.
The reason for this is that Mo levels are very low across both
deposits. However, further work should be undertaken to better
understand the distribution of Mo within the deposit.
Detailed downhole geophysics was collected from 15 drill holes
across the two prospects. This included 2 sets of in-situ bulk
density measurements (SSDG and BRDG). Both sets of data were
collected at 0.01m intervals. The data was loaded into Micromine,
composited to 1m intervals and averaged to provide an average bulk
density down hole. The density varied down hole and it was clear
that the mineralised skarn zones corresponded with elevated density
values. This average 1m density data was paired up with the flagged
composite assay file. As there was only data for some of the drill
holes an average density was determined for the fresh and oxide
mineralised domains for each deposit. At White Violet, a value of
3.16 g/cm(3) has been assigned to all fresh mineralisation and a
value of 1.95 g/cm(3) to all oxidised mineralisation. At Samarkand,
a value of 2.95 g/cm(3) has been assigned to all fresh
mineralisation and a value of 2.60 g/cm(3) to all oxidised
mineralisation.
There have been no direct measurements of any drill samples to
confirm the accuracy or appropriateness of this calibration.
However, the value for fresh mineralisation compares favourably
with the densities reported for the nearby Molyhil tungsten deposit
that is within the range of 2.78 - 3.5 g/cm(3) (based on an iron
grade calibration).
Classification criteria
The resource classification has been applied to the MRE based on
the drilling data spacing, grade and geological continuity, and
data integrity. Both White Violet and Samarkand models have low
levels of confidence in the estimation or potential impact of
modifying factors and have been classified as Inferred Mineral
Resources under JORC (2012). The classification reflects the view
of the Competent Person.
Mining and metallurgy
It has been assumed that the traditional open cut mining method
of drill, blast, load and haul will be used. No other mining
assumptions have been made.
No metallurgical recoveries have been applied to the Mineral
Resource Estimate.
Eventual economic extraction
It is the view of the Competent Person that at the time of
estimation there are no known issues that could materially impact
on the eventual extraction of the Mineral Resource.
The information contained within this announcement is deemed to
constitute inside information as stipulated under the Market Abuse
Regulations (EU) No. 596/2014. Upon the publication of this
announcement, this inside information is now considered to be in
the public domain.
Enquiries:
Mick Billing +61 (8) 7324 Thor Mining PLC Executive Chairman
1935
Ray Ridge +61 (8) 7324 Thor Mining PLC CFO/Company
1935 Secretary
Colin Aaronson/ +44 (0) 207 383 Grant Thornton UK LLP Nominated Adviser
Richard Tonthat/ Ben 5100
Roberts
Nick Emerson +44 (0) 1483 SI Capital Ltd Joint Broker
Claire Louise Noyce 413 500 Hybridan LLP Joint Broker
/ +44 (0) 203 764
John Beresford-Peirse 2341
Updates on the Company's activities are regularly posted on
Thor's website www.thormining.com, which includes a facility to
register to receive these updates by email, and on the Company's
twitter page @ThorMining.
Competent Persons Report
The information in this release that relates to the Estimation
and Reporting of Mineral Resources has been compiled by Dr Graeme
McDonald. Dr McDonald acts as an independent consultant to Thor
Mining PLC on the Bonya Mineral Resource estimation. Dr McDonald is
a member of the Australasian Institute of Mining and Metallurgy and
has sufficient experience with the style of mineralisation, deposit
type under consideration and to the activities undertaken to
qualify as a Competent Person as defined in the 2012 Edition of the
"Australasian Code for Reporting of Exploration Results, Mineral
Resources and Ore Reserves" (The JORC Code). Dr McDonald consents
to the inclusion in this report of the contained technical
information relating to the Mineral Resource Estimation in the form
and context in which it appears
The information in this report that relates to exploration
results is based on information compiled by Richard Bradey, who
holds a BSc in applied geology and an MSc in natural resource
management and who is a Member of The Australasian Institute of
Mining and Metallurgy. Mr Bradey is an employee of Thor Mining PLC.
He has sufficient experience which is relevant to the style of
mineralisation and type of deposit under consideration and to the
activity which he is undertaking to qualify as a Competent Person
as defined in the 2012 Edition of the 'Australasian Code for
Reporting of Exploration Results, Mineral Resources and Ore
Reserves'. Richard Bradey consents to the inclusion in the report
of the matters based on his information in the form and context in
which it appears.
JORC Code, 2012 Edition - Table 1 report template
Section 1 Sampling Techniques and Data
Criteria JORC Code explanation Commentary
-------------------------------------------------------------
Sampling Reverse Circulation drilling
techniques * Nature and quality of sampling (eg cut channels, with face sampling hammer
random chips, or specific specialised industry was used to obtain one
standard measurement tools appropriate to the metre interval samples.
minerals under investigation, such as down hole gamma
sondes, or handheld XRF instruments, etc). These Subsamples of approximately
examples should not be taken as limiting the broad 2-3kg were taken from each
meaning of sampling. interval using riffle splitter
for geochemical analysis.
XRF subsamples and chip
* Include reference to measures taken to ensure sample tray samples were collected,
representivity and the appropriate calibration of any logged and photographed.
measurement tools or systems used.
Industry standard QAQC
protocol was adopted with
* Aspects of the determination of mineralisation that reference material inserted
are Material to the Public Report. every fifth sample.
* In cases where 'industry standard' work has been done
this would be relatively simple (eg 'reverse
circulation drilling was used to obtain 1 m samples
from which 3 kg was pulverised to produce a 30 g
charge for fire assay'). In other cases more
explanation may be required, such as where there is
coarse gold that has inherent sampling problems.
Unusual commodities or mineralisation types (eg
submarine nodules) may warrant disclosure of detailed
information.
------------------ ------------------------------------------------------------- -----------------------------------
Drilling Reverse circulation drilling
techniques * Drill type (e.g. core, reverse circulation, open-hole with 3.5 inch face sampling
hammer, rotary air blast, auger, Bangka, sonic, etc) hammer.
and details (e.g. core diameter, triple or standard
tube, depth of diamond tails, face-sampling bit or
other type, whether core is oriented and if so, by
what method, etc).
------------------ ------------------------------------------------------------- -----------------------------------
Drill sample Samples were weighed from
recovery * Method of recording and assessing core and chip a selection of holes to
sample recoveries and results assessed. gauge sample recovery.
Samples were consistently
within the range of 15
* Measures taken to maximise sample recovery and ensure to 20kg and consistent
representative nature of the samples. across different rock units.
* Whether a relationship exists between sample recovery
and grade and whether sample bias may have occurred
due to preferential loss/gain of fine/coarse
material.
------------------ ------------------------------------------------------------- -----------------------------------
Logging Hole cuttings were logged
* Whether core and chip samples have been geologically geologically and photographed
and geotechnically logged to a level of detail to for the entire length of
support appropriate Mineral Resource estimation, each hole.
mining studies and metallurgical studies.
Mineralised and unmineralised
zones were easily determined
* Whether logging is qualitative or quantitative in from geological observations
nature. Core (or costean, channel, etc) photography. and XRF determination.
* The total length and percentage of the relevant
intersections logged.
------------------ ------------------------------------------------------------- -----------------------------------
Sub-sampling Subsamples for independent
techniques * If core, whether cut or sawn and whether quarter, laboratory analyses were
and sample half or all core taken. taken by riffle splitter.
preparation
The majority of samples
* If non-core, whether riffled, tube sampled, rotary were dry. Wet samples were
split, etc and whether sampled wet or dry. noted in the logs.
Sample size of 2-3kg is
* For all sample types, the nature, quality and appropriate for RC samples
appropriateness of the sample preparation technique. with a maximum particle
size of 6mm.
* Quality control procedures adopted for all For preliminary XRF determination
sub-sampling stages to maximise representivity of not to be used for resource
samples. estimation - a further
subsample of 30g was taken
which is not considered
* Measures taken to ensure that the sampling is representative.
representative of the in situ material collected,
including for instance results for field
duplicate/second-half sampling.
* Whether sample sizes are appropriate to the grain
size of the material being sampled.
------------------ ------------------------------------------------------------- -----------------------------------
Quality Laboratory geochemical
of assay * The nature, quality and appropriateness of the assay results have now
data and assaying and laboratory procedures used and whether been completed.
laboratory the technique is considered partial or total.
tests Industry standard sample
preparation finishing with
* For geophysical tools, spectrometers, handheld XRF sample pulverisation to
instruments, etc, the parameters used in determining 80% passing 75um. with
the analysis including instrument make and model, assay by peroxide fusion
reading times, calibrations factors applied and their and ICP-MS.
derivation, etc.
The technique is considered
appropriate for the analyte
* Nature of quality control procedures adopted (eg suite.
standards, blanks, duplicates, external laboratory
checks) and whether acceptable levels of accuracy (ie Industry standard QA/QC
lack of bias) and precision have been established. protocol is implemented
in the assay process.
------------------ ------------------------------------------------------------- -----------------------------------
Verification Significant intersections
of sampling * The verification of significant intersections by reported correspond with
and assaying either independent or alternative company personnel. visual indications in samples.
No further independent
verification has been undertaken.
* The use of twinned holes.
* Documentation of primary data, data entry procedures,
data verification, data storage (physical and
electronic) protocols.
* Discuss any adjustment to assay data.
------------------ ------------------------------------------------------------- -----------------------------------
Location All hole collar locations
of data * Accuracy and quality of surveys used to locate drill were surveyed by licenced
points holes (collar and down-hole surveys), trenches, mine survey contractor for mineral
workings and other locations used in Mineral Resource resource estimation.
estimation.
North seeking gyro will
be used for downhole survey.
* Specification of the grid system used.
Grid system used is GDA94,
zone 53.
* Quality and adequacy of topographic control.
------------------ ------------------------------------------------------------- -----------------------------------
Data spacing Drill holes are spaced
and distribution * Data spacing for reporting of Exploration Results. at 40 metre centres on
25 metre spaced drill sections.
This spacing is considered
* Whether the data spacing and distribution is appropriate for resource
sufficient to establish the degree of geological and estimation in this style
grade continuity appropriate for the Mineral Resource of mineralisation.
and Ore Reserve estimation procedure(s) and
classifications applied. Sample compositing was
undertaken in areas that
were not mineralised.
* Whether sample compositing has been applied.
------------------ ------------------------------------------------------------- -----------------------------------
Orientation Hole orientations are appropriate
of data * Whether the orientation of sampling achieves unbiased for the orientation of
in relation sampling of possible structures and the extent to target mineralised zones.
to geological which this is known, considering the deposit type.
structure
* If the relationship between the drilling orientation
and the orientation of key mineralised structures is
considered to have introduced a sampling bias, this
should be assessed and reported if material.
------------------ ------------------------------------------------------------- -----------------------------------
Sample The project is located
security * The measures taken to ensure sample security. in a remote region. No
unauthorised company personnel
visited the site during
operations. Assay samples
were collected from each
hole immediately after
drilling. Samples were
transported for safe storage
at a base camp before being
securely packaged for transport
to the laboratory. All
submitted assay samples
were receipted by the laboratory.
------------------ ------------------------------------------------------------- -----------------------------------
Audits None
or reviews * The results of any audits or reviews of sampling
techniques and data.
------------------ ------------------------------------------------------------- -----------------------------------
Section 2 Reporting of Exploration Results
Criteria JORC Code explanation Commentary
-----------------------------------------------------------------
Mineral tenement The Bonya deposits are
and land tenure * Type, reference name/number, location and ownership located
status including agreements or material issues with third on EL29701 jointly held
parties such as joint ventures, partnerships, by Arafura Resources
overriding royalties, native title interests, Limited
historical sites, wilderness or national park and (60%) and Thor Mining
environmental settings. PLC
(40%) with Thor acting
as
* The security of the tenure held at the time of manager.
reporting along with any known EL29701 is a mature
exploration
licence subject to
impediments to obtaining a licence ongoing
to operate in the area. biennial renewal.
------------------------ ----------------------------------------------------------------- -------------------------
Exploration Previous drilling was
done by other * Acknowledgment and appraisal of exploration by other undertaken
parties parties. by Central Pacific
Minerals
NL in 1971 using open
hole
percussion with limited
success. There are no
complete
records of the historic
drilling.
------------------------ ----------------------------------------------------------------- -------------------------
Geology Contact metamorphic
* Deposit type, geological setting and style of skarn
mineralisation. hosted scheelite.
------------------------ ----------------------------------------------------------------- -------------------------
Drill hole This information was
Information * A summary of all information material to the provided
understanding of the exploration results including a in THR announcement of
tabulation of the following information for all 8
Material drill holes: January 2020.
* easting and northing of the drill hole collar
* elevation or RL (Reduced Level - elevation above sea
level in metres) of the drill hole collar
* dip and azimuth of the hole
* down hole length and interception depth
* hole length.
* If the exclusion of this information is justified on
the basis that the information is not Material and
this exclusion does not detract from the
understanding of the report, the Competent Person
should
clearly explain why this is the case.
------------------------ ----------------------------------------------------------------- -------------------------
Data aggregation Where sample intervals
methods * In reporting Exploration Results, weighting averaging vary,
techniques, maximum and/or minimum grade truncations reported average grades
(eg cutting of high grades) and cut-off grades are are length weighted. No
usually Material and should be stated. grades were cut.
A 3-metre maximum waste
width and cut-off grade
* Where aggregate intercepts incorporate short lengths of 0.08% WO(3) was used
of high-grade results and longer lengths of low grade in determining
results, the procedure used for such aggregation aggregated
should be stated and some typical examples of such mineralisation
aggregations should be shown in detail. intervals.
High-grade intervals
were
* The assumptions used for any reporting of metal highlighted where WO(3)
equivalent values should be clearly exceeded 1%.
No metal equivalents
were
stated. reported.
------------------------ ----------------------------------------------------------------- -------------------------
Relationship Mineralisation
between mineralisation * These relationships are particularly important in the intercept
widths and reporting of Exploration Results. angles are in the order
of 60 degrees.
Correction
* If the geometry of the mineralisation with respect to to true widths is in
the drill hole angle is known, its the
order of 60 to 75% of
drill
widths. Estimated true
widths
were provided in THR
announcement
of 8 January 2020.
------------------------ ----------------------------------------------------------------- -------------------------
Section 3 Estimation and Reporting of Mineral Resources
(Criteria listed in section 1, and where relevant in section 2,
also apply to this section.)
Criteria JORC Code explanation Commentary
------------------------------------------------------------
Database
integrity * Measures taken to ensure that data has not been * A data check of source assay data and survey data has
corrupted by, for example, transcription or keying been undertaken and compared to the database. No
errors, between its initial collection and its use translation issues have been identified. The data was
for Mineral Resource estimation purposes. validated during the interpretation of the
mineralisation, with no significant errors
identified. Some recommendations for database
* Data validation procedures used. improvements have been made.
* Data validation processes are in place and run upon
import into Micromine to be used for the MRE. Checks
included: missing intervals, overlapping intervals
and any depth errors.
* A DEM topography to DGPS collar check has been
completed.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Site visits
* Comment on any site visits undertaken by the * No Site visits by the CP have been undertaken at this
Competent Person and the outcome of those visits. stage due to the current lack of field activity in
the area.
* If no site visits have been undertaken indicate why
this is the case.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Geological
interpretation * Confidence in (or conversely, the uncertainty of ) * The tungsten/copper mineralisation is predominantly
the geological interpretation of the mineral deposit. within a calc-silicate skarn often bounded by mafic
intrusive, granite and/or pegmatite. Mineralisation
also appears to form outside of these main
* Nature of the data used and of any assumptions made. calc-silicate skarns in sheared hornfels and
amphibolite. The primary tungsten bearing mineral is
scheelite. The geological interpretation appears to
* The effect, if any, of alternative interpretations on be sound and based on good field-based evidence and
Mineral Resource estimation. relationships.
* The use of geology in guiding and controlling Mineral * Reverse circulation drill holes have been used in the
Resource estimation. MRE. Lithology, structure, alteration and
mineralisation data has been used to generate the
mineralisation model. The primary assumption is that
* The factors affecting continuity both of grade and the mineralisation is hosted within structurally
geology. controlled locations associated with a steeply
dipping shear zone.
* Due to the relatively close spaced nature of the
drilling data and the preliminary nature of the
project, no alternative interpretations have been
considered at this stage.
* The mineralisation interpretation is based on a WO(3)
cut-off grade of 0.05% for White Violet and 0.01% for
Samarkand.
* A single grade domain has been identified and
estimated at White Violet while 4 separate domains
have been interpreted at Samarkand.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Dimensions
* The extent and variability of the Mineral Resource * At White violet the mineralised domain is up to 140m
expressed as length (along strike or otherwise), plan in length and width of approximately 20m. At
width, and depth below surface to the upper and lower Samarkand the zone of mineralisation is up to 190m in
limits of the Mineral Resource. length and approximately 30m in width.
* At both deposits the mineralisation outcrops and has
been modelled to a depth of 180m below surface at
White Violet and 115m below surface at Samarkand.
* The mineralisation in both cases dips steeply at
approximately 85 degrees to the south south west.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Estimation and
modelling * The nature and appropriateness of the estimation * Grade estimation at White Violet for WO(3) and Cu was
techniques technique(s) applied and key assumptions, including been completed using Ordinary Kriging (OK) into a
treatment of extreme grade values, domaining, single mineralised domain using Micromine software.
interpolation parameters and maximum distance of Variography was been undertaken on the grade domain
extrapolation from data points. If a computer composite data. Variogram orientations are largely
assisted estimation method was chosen include a controlled by the strike and dip of the
description of computer software and parameters used. mineralisation.
* The availability of check estimates, previous * Grade estimation at Samarkand for WO(3) and Cu was
estimates and/or mine production records and whether completed using the Inverse Distance squared (ID2)
the Mineral Resource estimate takes appropriate technique.
account of such data.
* There have been no previous estimates at either
* The assumptions made regarding recovery of deposit. A check estimate using an alternative
by-products. estimation technique (ID2) was also undertaken at the
White Violet deposit.
* Estimation of deleterious elements or other non-grade
variables of economic significance (eg sulphur for * No assumptions have been made regarding recovery of
acid mine drainage characterisation). any by-products.
* In the case of block model interpolation, the block * The data spacing varies across the deposits but with
size in relation to the average sample spacing and a nominal drill hole spacing of 25 m by 10 m. A
the search employed. parent block size of 8m (X) by 4m (Y) by 8m (Z) with
a sub-block size of 2m (X) by 1m (Y) by 2m (Z) has
been used at White Violet to define the
* Any assumptions behind modelling of selective mining mineralisation. At Samarkand a parent block size of
units. 4m (X) by 8m (Y) by 8m (Z) with a sub-block size of
1m (X) by 2m (Y) by 2m (Z) was used. WO(3) and Cu
estimated at the parent block scale.
* Any assumptions about correlation between variables.
o Pass 1 estimation has been
* Description of how the geological interpretation was undertaken using a minimum of
used to control the resource estimates. 4 and a maximum of 16 samples
into a search ellipse with a
radius of 50m for White Violet
* Discussion of basis for using or not using grade and 60m for Samarkand, with samples
cutting or capping. from a minimum of two drill holes.
o Pass 2 estimation has been
undertaken using a minimum of
* The process of validation, the checking process used, 4 and a maximum of 16 samples
the comparison of model data to drill hole data, and into a search ellipse with a
use of reconciliation data if available. radius of 120m for White Violet
and 140m for Samarkand, with
samples from a minimum of two
drill holes.
o Pass 3 estimation has been
undertaken using a minimum of
4 and a maximum of 16 samples
into a search ellipse with a
radius of 200m for White Violet
and 250m for Samarkand, with
samples from a minimum of one
drill hole.
* No selective mining units are assumed in this
estimate.
* WO(3) and Cu have been estimated within the
mineralised domains. No correlation between variables
has been assumed.
* The mineralisation and geological wireframes have
been used to flag the drill hole intercepts in the
drill hole assay file. The flagged intercepts have
then been used to create composites in Micromine. The
composite length is 1 m in all data.
* The influence of extreme sample distribution outliers
in the composited data has been determined using a
combination of histograms and log probability plots.
It was decided that top-cuts need to be applied as
follows: White Violet, WO(3) - 1.5% Cu - 0.5%,
Samarkand, WO(3) - 1.45% Cu - 1.5%
* Model validation has been carried out, including
visual comparison between composites and estimated
blocks; check for negative or absent grades;
statistical comparison against the input drill hole
data and graphical plots.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Moisture
* Whether the tonnages are estimated on a dry basis or * The tonnes have been estimated on a dry basis.
with natural moisture, and the method of
determination of the moisture content.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Cut-off
parameters * The basis of the adopted cut-off grade(s) or quality * For the reporting of the Mineral Resource Estimate, a
parameters applied. 0.05% WO(3) cut-off has been used at both White
Violet and Samarkand in consultation with Thor.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Mining factors
or assumptions * Assumptions made regarding possible mining methods, * It has been assumed that the traditional open cut
minimum mining dimensions and internal (or, if mining method of drill, blast, load and haul will be
applicable, external) mining dilution. It is always used.
necessary as part of the process of determining
reasonable prospects for eventual economic extraction
to consider potential mining methods, but the * No other assumptions have been made at this time.
assumptions made regarding mining methods and
parameters when estimating Mineral Resources may not
always be rigorous. Where this is the case, this
should be reported with an explanation of the basis
of the mining assumptions made.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Metallurgical
factors or * The basis for assumptions or predictions regarding * No metallurgical recoveries have been applied.
assumptions metallurgical amenability. It is always necessary as
part of the process of determining reasonable
prospects for eventual economic extraction to * It is assumed that processing would be undertaken at
consider potential metallurgical methods, but the the proposed nearby processing facility at Thor's
assumptions regarding metallurgical treatment Molyhil project.
processes and parameters made when reporting Mineral
Resources may not always be rigorous. Where this is
the case, this should be reported with an explanation
of the basis of the metallurgical assumptions made.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Environmental
factors or * Assumptions made regarding possible waste and process * No environmental assumptions have been made during
assumptions residue disposal options. It is always necessary as the MRE.
part of the process of determining reasonable
prospects for eventual economic extraction to
consider the potential environmental impacts of the
mining and processing operation. While at this stage
the determination of potential environmental impacts,
particularly for a greenfields project, may not
always be well advanced, the status of early
consideration of these potential environmental
impacts should be reported. Where these aspects have
not been considered this should be reported with an
explanation of the environmental assumptions made.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Bulk density
* Whether assumed or determined. If assumed, the basis * There have been no direct measurements of any drill
for the assumptions. If determined, the method used, samples at the White Violet or Samarkand deposits.
whether wet or dry, the frequency of the measurements Detailed downhole geophysics was collected from 15
, drill holes across the two prospects. This included 2
the nature, size and representativeness of the sets of in-situ bulk density measurements (SSDG and
samples. BRDG). Both sets of data were collected at 0.01m
intervals. The data was loaded into Micromine,
composited to 1m intervals and averaged to provide an
* The bulk density for bulk material must have been average bulk density down hole. The density varied
measured by methods that adequately account for void down hole and it was clear that the mineralised skarn
spaces (vugs, porosity, etc), moisture and zones corresponded with elevated density values. This
differences between rock and alteration zones within average 1m density data was paired up with the
the deposit. flagged composite assay file. As there was only data
for some of the drill holes an average density was
determined for the fresh and oxide mineralised
* Discuss assumptions for bulk density estimates used domains for each deposit. At White Violet, a value of
in the evaluation process of the different materials. 3.16 g/cm(3) has been assigned to all fresh
mineralisation and a value of 1.95 g/cm(3) to all
oxidised mineralisation. At Samarkand, a value of
2.95 g/cm(3) has been assigned to all fresh
mineralisation and a value of 2.60 g/cm(3) to all
oxidised mineralisation.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Classification
* The basis for the classification of the Mineral * The resource classification has been applied to the
Resources into varying confidence categories. MR estimate based on the drilling data spacing, grade
and geological continuity, and data integrity.
* Whether appropriate account has been taken of all
relevant factors (ie relative confidence in * The classification takes into account the relative
tonnage/grade estimations, reliability of input data, contributions of geological and data quality and
confidence in continuity of geology and metal values, confidence, as well as grade confidence and
quality, quantity and distribution of the data). continuity.
* Whether the result appropriately reflects the * The classification reflects the view of the Competent
Competent Person's view of the deposit. Person.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Audits or
reviews * The results of any audits or reviews of Mineral * This Mineral Resource estimate has not been audited
Resource estimates. by an external party.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
Discussion of
relative * Where appropriate a statement of the relative * The relative accuracy of the Mineral Resource
accuracy/ accuracy and confidence level in the Mineral Resource estimate is reflected in the reporting of the Mineral
confidence estimate using an approach or procedure deemed Resource as per the guidelines of the 2012 JORC Code.
appropriate by the Competent Person. For example, the
application of statistical or geostatistical
procedures to quantify the relative accuracy of the * The statement relates to global estimates of tonnes
resource within stated confidence limits, or, if such and grade.
an approach is not deemed appropriate, a qualitative
discussion of the factors that could affect the
relative accuracy and confidence of the estimate. * No production records have been supplied as part of
the scope of works, so no comparison or
reconciliation has been made. Historically, only a
* The statement should specify whether it relates to small amount of copper has been produced from shallow
global or local estimates, and, if local, state the pits.
relevant tonnages, which should be relevant to
technical and economic evaluation. Documentation
should include assumptions made and the procedures
used.
* These statements of relative accuracy and confidence
of the estimate should be compared with production
data, where available.
--------------- ------------------------------------------------------------ --------------------------------------------------------------
This information is provided by RNS, the news service of the
London Stock Exchange. RNS is approved by the Financial Conduct
Authority to act as a Primary Information Provider in the United
Kingdom. Terms and conditions relating to the use and distribution
of this information may apply. For further information, please
contact rns@lseg.com or visit www.rns.com.
END
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