REG - Great Western Mining - Mineral Resource Estimate

Great Western MiningAnnouncement

09/11/2022 07:01

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RNS Number : 7188F  Great Western Mining Corp. plc  09 November 2022

 

GREAT WESTERN MINING CORPORATION PLC

("Great Western" or the "Company")

 

Mineral Resource Estimate and Exploration Target

Olympic and Mineral Jackpot Projects, Nevada, USA

 

Great Western Mining Corporation PLC (AIM - GWMO, Euronext Growth - 8GW),
which is exploring and developing gold, silver and copper targets in Nevada,
is pleased to announce the results of an independent initial Mineral Resource
Estimate for the Olympic Gold Tailings project as well as Exploration Targets
for stockpile and spoil material at the Olympic Gold Project and Mineral
Jackpot Project, Nevada USA.  All resources and exploration targets are
reported in accordance with the JORC code (2012).

 

HIGHLIGHTS

·    Inferred Resource Estimate of 31,000 tonnes, grading 1.6 g/t Au and
3.0 g/t Ag in tailings at Olympic Mine.

·    Exploration Target of 3,400 - 6,400 tonnes grading between 0.5 and
1.2 g/t Au and 1.2 and 2.1 g/t Ag in the substrate beneath the tailings volume
at the Olympic Mine.

·    Exploration Target of 9,000 - 12,000 tonnes grading between 0.9 and
2.4 g/t Au and 2.0 and 5.1 g/t Ag in a coarse stockpile at Olympic Mine.

·    Exploration Target of 4,200 - 7,700 tonnes grading between 40 and 140
g/t Ag and 0.3 and 0.3 g/t Au in spoil heaps at Mineral Jackpot.

 

Note 1 - g/t = grams per metric tonne, equivalent to parts per million

 

 

Great Western chairman Brian Hall commented: "This independent assessment of
the pre-mined material so far identified on our claim groups in Nevada
strongly reinforces our confidence in being able to generate revenues from
gold and silver through the Western Milling LLC joint venture recently
announced.  We will keep shareholders informed regularly as the mill
development project progresses."

 

OVERVIEW

Below are the results of an independent Initial Mineral Resource Estimate
['MRE') for the Olympic Gold Tailing project together with Exploration Targets
for stockpile and spoil material at the Olympic Gold Project and Mineral
Jackpot group of claims, all reported in accordance with JORC code (2012) and
prepared by independent consultant Addison Mining Services Limited ('AMS').

This MRE, effective as of 4 May 2022 for the Olympic Tailings Project
comprises:

·    An Inferred Mineral Resource of approximately 31,000 tonnes grading
1.6 g/t Au and 3.0 g/t Ag for 1,600 troy ounces of Au metal and 3,000 ounces
of Ag metal (see the following table).

Table 1: Olympic Tailings Inferred Mineral Resource, reported globally (no
cut-off grade)

 Area               Au      Ag      Volume   Density (g/cm(3))  Tonnage  Au Metal  Ag Metal

(g/t)
(g/t)
(m(3))
(t)
(ozt)
(ozt)
 Main tailing pad   1.62    2.91    21,000   1.42               29,000   1,500     2,700
 Minor tailing pad  1.65    6.92    1,200    1.42               1,800    100       400
 TOTAL              1.6     3.0     22,000   1.42               31,000   1,600     3,000

 

In addition to the Mineral Resources set out above, Exploration Targets are
presented as a range of grades and tonnages where insufficient exploration has
been completed to allow estimation and reporting of a Mineral Resource in
accordance with the JORC code (2012). These estimates are therefore conceptual
in nature. Full details of these targets are presented in tables below.
 Summary details of the targets are:

·    Material underlying the Olympic tailings: 3,400 - 6,400 tonnes
grading between 0.5 and 1.2 g/t Au and 1.2 and 2.1 g/t Ag.

·    Olympic Mine coarse stockpile: 9,000 - 12,000 tonnes grading between
0.9 and 2.4 g/t Au and 2.0 and 5.1 g/t Ag.

·    Mineral Jackpot spoil heaps: 4,200 - 7,700 tonnes grading between 40
and 140 g/t Ag and 0.3 and 0.3 g/t Au.

Table 2: Exploration Target for material underlying the Olympic tailings
resource.

 Scenario      Thickness (m)  Au      Ag      Volume  Tonnage  Au Metal  Ag Metal

(g/t)
(g/t)
(m3)

                                                      (t)      (ozt)     (ozt)
 Conservative  0.3            0.5     1.2     2,400   3,400    50        150
 Pragmatic     0.5            0.8     1.6     3,500   4,900    150       250
 Optimistic    0.6            1.2     2.1     4,500   6,400    250       400

 

Table 3: Exploration Targets in the Stockpile at Olympic.

 Scenario      Au      Ag      Volume (m3)  Density (g/cm3)  Tonnage (t)  Au Metal (ozt)  Ag Metal (ozt)

               (g/t)   (g/t)
 Conservative  0.9     2.0     6,500        1.40             9,000        300             600
 Pragmatic     1.7     3.7     6,500        1.60             10,000       600             1,200
 Optimistic    2.4     5.1     6,500        1.80             12,000       900             1,900

 

Table 4: Exploration Target for Spoil Heaps at Mineral Jackpot.

 Scenario      Au      Ag      Volume (m3)  Density (g/cm3)  Tonnage (t)  Au Metal (ozt)  Ag Metal (ozt)

(g/t)
(g/t)
 Conservative  0.3     40      3,000        1.40             4,200        30              5,500
 Pragmatic     0.3     75      4,300        1.60             6,900        50              17,000
 Optimistic    0.3     140     4,300        1.80             7,700        60              35,000

 

 

 

Competent Person's Inferred Mineral Resource Estimate and Exploration Targets,
reported in accordance with the JORC Code (2012 edition)

Following drilling and sampling conducted in 2021 and 2022, the Company
commissioned AMS to conduct an independent Mineral Resource Estimate together
with outline Exploration Target potential. Estimates are based on all the
available data from the tailings, stockpiles and waste dumps collected up to 4
May 2022.

The MRE and Exploration Targets have been reported in accordance with the
Joint Ore Reserve Committee (JORC) code, 2012 edition.

Summary of Resource Estimate and Reporting Criteria

In accordance with the JORC code (2012), a summary of the material information
used to estimate the initial MRE and Exploration Targets is set out below. For
further detail please refer to the JORC (2012) Table 1, set out in the
appendix to this announcement. Both the appendix and the supporting images can
be found at the following link:
https://www.greatwesternmining.com/greatwesternmining-com/_img/pdf/TableOneAndFigures.pdf
(https://www.greatwesternmining.com/greatwesternmining-com/_img/pdf/TableOneAndFigures.pdf)

 

Geological Interpretation

As discussed above, the resources and exploration targets covered by this
release are in pre-mined material - tailings, stockpiles and spoil heaps. A
summary of the geology of the deposits mined for this material is as follows:

Olympic

The OMCO vein, which was mined between 1916 and 1942, is a low sulphidation
epithermal gold vein hosted in a late Early Miocene rhyolitic volcanic
sequence.

Mineral Jackpot

The workings at Mineral Jackpot were developed along an array of parallel
quartz veins hosted in a Cretaceous granite batholith.

Input Data Summary

The MRE is based on all the available data from the tailings collected up to 4
May 2022 and includes information from 23 auger drillholes totalling 93 m and
33 surface grab samples.

A total of 20 drillholes were completed over the main tailings pad which has a
surface area of approximately 7160 m(2). The spacing between drillholes is
irregular (10 - 30 m between collars except for a pair of holes drilled to
check close-range variability which are 4 m apart), with more dense coverage
in the southern part of the pad. In addition, 24 surface grab samples were
collected in the main tailings area which were taken into consideration for
the MRE.

The minor tailings pad is located approximately 20 m to the south of the main
tailings area. A total of two drillholes were completed over minor tailings
which has a surface area of approximately 550 m(2). Both drillholes are
located in the west part of the tailings with 10 m spacing between them.
Additionally, nine surface grab samples were collected from the minor tailings
area and taken into consideration for the MRE.

The distribution of drillholes within the tailings area is sufficient to
establish the degree of geological and grade continuity appropriate for
classification of Inferred Resources as defined by the JORC (2012) code.

An exploration target in the horizon underlying the tailings, which is
dominantly clay material, was also identified based on the drilling dataset
described above, but there was insufficient data to estimate a mineral
resource.

An exploration target in the stockpile was identified based on four vertical
RC drillholes, of which two were twinned, covering the central part of the
stockpile. Additionally, six surface bulk samples were collected in that area.
The stockpile has an approximate surface area of 2,000 m(2) and drillhole and
surface samples are distributed over the major part of the area. There was
insufficient data to estimate a mineral resource.

An exploration target in the Mineral Jackpot (MJ) Prospect was determined over
44 spoil heaps identified in the field and modelled via deviation of the heap
from the surrounding land surface. Spoil heaps were identified and mapped over
an area of 1 km(2).  However, heaps located in only a part of this area
(approximately 400 m x 350 m) were sampled. In total 22 bulk surface samples
were collected, of which 16 were unique and six were field duplicates. There
was insufficient data to estimate a mineral resource.

Sampling and Sub-Sampling Techniques

All samples were submitted to the lab from the field.

·    For the tailings pad drilling, sample intervals were typically 2 ft
(0.61 m), with a range of 1‑3 ft (0.30 - 0.91 m).

·    The coarse stockpile was drilled with a reverse circulation (RC)
drill rig. Each of the four holes rendered one bulk sample.

·    The Mineral Jackpot spoil heap bulk samples were each in the range of
15-25 kg.

Both labs used were ISO17025 accredited and used similar preparation and
analytical techniques. Samples were crushed until 70% or more of the material
passed a 2 mm sieve, then this material was split down to a 250 g sample and
pulverised until 85% or more of this passed a 75 µm sieve. This master pulp
was then analysed via fire assay for gold and ICP-OES for a 35-element suite.

Sample Recovery

Sample recovery was not directly measured for RC and auger drillholes.
 However, geologists present during drilling observed the quantity of
material being produced from the drill rigs per metre, noting any drops in
recovery. In the case of the stockpile, drilling lower sample mass was
attributed to void space. The recovery of the auger drilling over the tailings
was reported by Great Western to be excellent with no notable areas of poor
recovery.

Data Verification

The drill hole data were validated using Micromine's drill hole database
validation tools. The database was checked for errors such as overlapping
intervals, intervals beyond drill hole collar depth, missing intervals,
missing drill holes and large deviations in drill hole surveys. The drill hole
traces were also visually inspected. The spatial location of surface samples
was visually checked and compared to the location of 3D wireframes. Some
samples were noted to be plotting outside the wireframe, especially on small
spoil heaps. Those variations are due to the inaccuracy of handheld GPS and
accepted after consultation with the Company's geological team. Additionally,
10% of the total samples were cross checked with original assay certificates.
A small number of minor errors were detected in drilling data and corrected
via consultation with the Company's geological team.

The drillhole database is considered by the Competent Person to be robust and
fit for purpose in Mineral Resource Estimation.

Estimation Methodology

Solids for the main and minor tailings pads were created based on lithological
contacts of tailings material and underlaying layer. Wireframes were manually
generated in Micromine and restricted to a DTM generated from a drone survey
with ~0.5 m accuracy.

Analysis of surface samples indicated potential Au and Ag enrichment on the
top layer of the tailings material. Surface samples were collected up to 15 cm
into the ground, hence two domains were established - top 15 cm of the solid
and the part below that. Those domains were established for both main and
minor tailings. Original solids were then split into two parts using Boolean
operations with the DTM dropped by 15 cm. The grade within the volumes was
averaged using length-weighted averaging. Sensitivity to data clustering was
also investigated but not considered to be material.

For exploration targets of the Olympic stockpile and Mineral Jackpot spoil
heaps, volumes were estimated from mapping and digital terrain models. The
tonnage range was estimated based on variable bulk density and the grades were
estimated based on the distribution of the assay data and assessment of one
standard deviation about the mean. In the case of Mineral jackpot, the volume
was further ranged by removing 30% of the spoil heaps from the estimate.

For all estimates a length or mass-weighted average was used in assessment of
the grades. One sample was capped at 10 g/t Au in the tailings estimate.

Bulk Density

The database contains 12 bulk density measurements in the Olympic tailings of
which nine were taken from surface and three from downhole material. For the
purpose of Mineral Resource Estimation, the tailings material was assigned a
bulk density of 1.42 g/cm(3). For the other prospects, variable density values
from conservative to optimistic, based on comparable material elsewhere, were
used to calculate the tonnage ranges of the exploration targets.

Classification Criteria

Based on the data available, it is the Competent Person's opinion that a
classification of Inferred is warranted for the major and minor tailings at
Olympic. Further sampling to better understand grade variability is required
to allow classification of Indicated Resources. The material immediately
underlying the tailings does not have sufficient sampling and volumetric
control to allow classification of a Resource and is reported as an
exploration target. Similarly, further sampling is required to understand the
grade variability of the Olympic stockpile and Mineral Jackpot spoil heaps and
consequently these are reported as exploration targets.

Reasonable Prospect of Eventual Economic Extraction

No calculation of an economic cut-off grade has been undertaken for the
Olympic Tailings Resource. It is anticipated that no selective mining would be
undertaken and the Resource is reported globally (no cut-off grade). The
average grade above cut-off is considered by the Competent Person to have a
reasonable prospect of eventual economic extraction, assuming that
metallurgical recoveries greater than 20% may be achieved.

Environmental and Social Considerations

Both sites are remote from habitation and represent a minimum of potential
disturbance for local neighbours. Both sites are existing mine sites, so
further work, particularly the extraction of mine waste material when managed
sensitively, can be considered an improvement.

Care must be taken in driving to Olympic as the route passes an isolated
ranch, and cattle are often found near the main track. Similar considerations
occur on the route to Mineral Jackpot where the low-level access road passes
through the Marietta Wild Burro Range.

Independent Competent Person's Statement

The Olympic Tailings Inferred Resource Estimate, Olympic Coarse Stockpile and
Mineral Jackpot Spoil Heaps Exploration Targets were prepared by Mr R. J.
Siddle, MSc, MAIG, Principal Resource Geologist and Director of Addison Mining
Services Ltd. and Competent Person. Mr. Siddle is an independent Competent
Person within the meaning of the JORC (2012) code. Mr. Siddle has reviewed and
verified the technical information that forms the basis of, and has been used
in the preparation of, the Mineral Resource Estimate and this announcement,
including analytical data, drill hole logs, QC data, density measurements and
sampling practice.  Mr. Siddle was assisted in the study by Ms. Paula
Mierzwa, MSc., who worked under the supervision of the Competent Person.  Mr.
Siddle consents to the inclusion in this announcement of the matters based on
the information, in the form and context in which it appears. Mr. Siddle has
also reviewed and approved the technical information in his capacity as a
Competent Person as defined by the JORC code (2012).

Qualified Person's Statement (for Great Western)

The information in this announcement that relates to exploration results is
based on information reviewed by Dr James Blight MGeol PhD MAusIMM (CP) who is
Exploration Manager of Great Western Mining PLC.  Dr Blight has requisite
experience 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'.
Dr Blight is also a "Qualified Person" as defined in the "Note for Mining and
Oil & Gas Companies" which form part of the AIM Rules for Companies. Dr
Blight has reviewed and consented to the inclusion in the announcement of the
information in the form and context in which it appears.

 

MARs Statement:  This press release contains inside information as defined in
Article 7(1) of the Market Abuse Regulations.

 

For further information:

 

 Great Western Mining Corporation PLC
 Brian Hall, Chairman                                              +44 207 933 8780
 Max Williams, Finance Director                                    +44 207 933 8780

 Davy (NOMAD, Euronext Growth Listing Sponsor & Joint Broker)

 Brian Garrahy                                                     +353 1 679 6363

 Novum Securities (Joint Broker)

 Jon Belliss                                                       +44 207 399 9400

 Walbrook PR (PR advisers)

 Nick Rome/Joe Walker                                              +44 207 933 8783

 

Notes to Editors

The Company has a large acreage position in Mineral County, Nevada. The area
consists of rugged, mountainous terrain, which means that large parts of it
remain under-explored. Mineral potential is hosted by the regional Walker Lane
Structural Belt, the largest structural and metallogenic belt in Nevada, yet
one of the least explored in recent times, with gold, silver and copper
currently produced in Mineral County.  Great Western has seven distinct
concession areas which offer the potential for exploiting (1) short term gold
and silver deposits and (2) long-term, world-class copper deposits.

Six of the Company's properties are in the west of Mineral County and are 100%
owned and operated.  The Company has an option to acquire a seventh property,
the Olympic Gold Project, in the east of the county.  Great Western's small
exploration team is supported by locally based consultants and contractors.

The state of Nevada is generally considered to be one of the world's most
mining friendly jurisdictions.  While tightly regulated and environmentally
conscious, Nevada welcomes the mining industry.  Great Western takes care to
ensure that its claims are maintained in good standing and all regulations
observed.

There are numerous gold and silver prospects on the Company's acreage,
including extensive historic mine workings which offer the opportunity for
secondary recovery.

Furthermore, through extensive drilling over a five-year period, Great Western
has established a Mineral Resource on its first target area known as M2, of
4.3 million tonnes at 0.45% copper, for 19,000 tonnes of contained copper
metal. This resource has been independently reported in accordance with JORC
guidelines.

 

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