REG - Great Southrn.Copper - Completion of Geophysical Surveys at Cerro Negro

Great Southern CopperAnnouncement

Mon 07:00

For best results when printing this announcement, please click on link below:
https://newsfile.refinitiv.com/getnewsfile/v1/story?guid=urn:newsml:reuters.com:20250714:nRSN8981Qa&default-theme=true

RNS Number : 8981Q  Great Southern Copper PLC  14 July 2025

 

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION AS STIPULATED UNDER THE UK
VERSION OF THE MARKET ABUSE REGULATION NO 596/2014 WHICH IS PART OF ENGLISH
LAW BY VIRTUE OF THE EUROPEAN (WITHDRAWAL) ACT 2018, AS AMENDED.  ON
PUBLICATION OF THIS ANNOUNCEMENT VIA A REGULATORY INFORMATION SERVICE, THIS
INFORMATION IS CONSIDERED TO BE IN THE PUBLIC DOMAIN.

 

 

14 July 2025

 

Great Southern Copper plc

("GSC" or the "Company")

 

Gradient Array IP Anomaly Extends for 2.5km South of Mostaza Cu-Ag Mine

 

Results define high priority Phase III drill targets for potential extensions
of Cu-Ag Mineralisation

 

Great Southern Copper plc (LSE: GSCU), the company focused on
copper-gold-silver exploration in Chile, is pleased to announce the completion
of ground geophysical surveys at the Cerro Negro prospect. Initial results
from the Gradient Array induced polarisation (IP) survey define multiple
geophysical targets along trend south of the mine.

 

Highlights:

·    Geophysical surveys completed at Cerro Negro in advance of Phase III
drilling

·  Gradient array IP chargeability highs correlate closely with known Cu-Ag
sulphide mineralisation intersected in previous GSC drilling(1,2,3,4)

·    Chargeability anomalies correlate with low resistivity, indicative of
hydrothermal alteration

·    Results define a 2.5km long anomalous trend to the south of the
Mostaza Cu-Ag mine which remains open

·    The geophysical anomalies are coincident with anomalous surface rock
chip geochemistry(5)

·    Processing and interpretation of Pole-Dipole IP (PDIP) and
Audio-frequency magneto-telluric (AMT) survey results are awaited

·    Phase III drilling preparation is well advanced

·    GSC holds option to own 100% of the Cerro Negro prospect, including
the Mostaza mine

·    Prospect located at low elevation with excellent access to
infrastructure and mining services

·    To prioritise Especularita, GSC will not proceed with the option
agreements at the San Lorenzo Cu-Au and Monti Li projects

 

Sam Garrett, Chief Executive Officer of Great Southern Copper, said: "The
preliminary results of the gradient array IP survey define a 2.5km long
anomaly south of the Mostaza mine, which is consistent with the results of the
Company's earlier rock sampling and mapping results.

 

"This is an exciting development and confirms significant potential for the
Mostaza copper-silver mineralisation to extend southward along the Mostaza
Fault Zone. We eagerly await the final results of the AMT and pole-dipole IP
surveys, which will provide critical insights to support us in finalising
plans for our Phase III exploration drilling at Cerro Negro.

 

"The exploration results across the Especularita project are both compelling
and transformative, advancing the project significantly. As such, the Company
has decided to prioritise its spending focus at Especularita and will not
proceed further with its San Lorenzo and Monti projects. With capital raising
conditions still challenging, this is considered to be the most effective
solution for maximising the potential of this opportunity."

Geophysics Survey Details:

 

A total of 2.44 line-kilometres of Pole-Dipole and Gradient Array IP surveys
were completed at the Cerro Negro prospect by Southern Rock Geophysics (SRG)
of Santiago, Chile. AMT data was also acquired along the same survey lines.
The survey consisted of five lines, each ranging from 440 to 600 metres (m) in
length (see Figure 1). Lines 2, 3, 4 and 5 were oriented east-west,
perpendicular to the primary north-south mineralisation trend. Line 1 was
aligned northwest-southeast, targeting beneath the historic Mostaza Mine while
avoiding stockpiled ore and pit walls. The survey was designed to identify the
potential for the Mostaza-style Cu-Ag mineralisation to extend south of the
open pit, where outcropping alteration and anomalous rock geochemistry define
a structurally-controlled mineralised trend. Results will assist in defining
Phase III drill targets along and adjacent to the Mostaza Fault that correlate
with the known mineralised lenses identified by mapping and sampling(5).

 

Preliminary results include plan maps for the Gradient Array IP. 2D inversion
model sections and 3D inversion for the PDIP and AMT data are in process.
Results are pending and will be integrated into the ongoing interpretation
once available. Detailed interpretation by GSC and SRG, including the use of
petrophysical properties testing of drillcore samples and predictive forward
modelling, will be conducted once the full results are received.

 

Gradient Array IP Survey Results:

 

Gradient Array IP provides a 2D plan-view representation of electrical
properties in the near surface. These include chargeability, which may
indicate the presence of sulphide minerals and resistivity, which can reflect
different rock types and their alteration.

 

At Cerro Negro, areas of high chargeability up to 12 milliseconds (see Figure
1) coincide with known mineralisation tested by drilling beneath the Mostaza
Mine (Line 1) and the mineralisation intersected in hole DD007 (Line 2). In
addition to these confirmed zones, the survey identified undrilled
chargeability anomalies on Lines 3 and 4, located approximately 1km and 2km
south of the mine, where previously reported surface rock-chip geochemistry
returned highly anomalous values of Cu and Ag(5).

 

Zones of low resistivity (see Figure 2) are spatially coincident with the
chargeability highs, consistent with the presence of altered host rocks. Areas
of high resistivity to the east and west of the central anomaly zone are
interpreted to represent less altered, and hence more resistive lithologies.

 

Together, the chargeability and resistivity data define a coherent 2.5km-long
anomaly consistent with the trend of the Mostaza Fault Zone, highlighting
multiple high-priority targets for follow-up drilling.

 

The results suggest that further survey lines to the south and north may be
considered for the future, as well as in-fill lines and extensions of existing
lines further to the east, where mapping has identified anomalous Cu-Ag hosted
in sub-parallel structures with evidence of artisanal mining.

 

 

 

 

 

Figure 1: Cerro Negro Prospect. Plan of gradient array results for
chargeability (top) and apparent resistivity (bottom).

 

San Lorenzo Cu-Au and Monti Li Projects:

 

Given the recent success of the exploration work at Especularita and the
strong outlook for future exploration programmes there, GSC has made a
strategic decision to prioritise capital deployment to Especularita. As a
result, the Company will not proceed with the San Lorenzo and Monti option
agreements. GSC will continue to assess new exploration and business
opportunities that are aligned with the Company's investment strategy both in
Chile and further afield as and when such opportunities arise.

 

  References:

1.    RNS 5182Y (26 Feb 2025): Cerro Negro assays return 20m of 3.3% Cu,
270g/t Ag

2.    RNS 9022A (17 Mar 2025): Exceptional results confirm potential of
Mostaza

3.    RNS 8896D (07 Apr 2025): Further exceptional assay results from
Mostaza

4.    RNS 1375O (24 June 2025): Exceptional Drilling Results Continue at
Mostaza (https://irtools.co.uk/82/story/f5b66dcf-4cf8-4edd-8484-c582235ad460)

5.   RNS 3120K (31 Oct 2024): Cerro Negro Exploration Results Up To 4.64% Cu
and 177ppm Ag

 

 

Enquiries:

 

 Great Southern Copper plc             c/o BlytheRay
 Sam Garrett, Chief Executive Officer  +44 (0) 20 7138 3204

 SI Capital Limited
 Nick Emerson                          +44 (0) 1483 413500

 BlytheRay
 Tim Blythe / Megan Ray                +44 (0) 20 7138 3204

                                       GSC@blytheray.com

 

Notes for Editors:

 

About Great Southern Copper

 

Great Southern Copper PLC is a UK-listed mineral exploration company focused
on the discovery of copper-gold-silver deposits in Chile. The Company has the
option to acquire mining rights to 100% of Especularita project in the
under-explored coastal belt of Chile that is prospective for large scale
copper-gold-silver deposits. Chile is a globally significant mining
jurisdiction being the world's largest producer and exporter of copper.

 

The Especularita Project is located in the coastal metallogenic belt of Chile
which hosts significant copper mines and deposits, including Teck's Carmen de
Andacollo copper mine, and boasts excellent access to infrastructure such as
roads, power and ports. Significant historical small-scale and artisanal
workings for both copper and gold are readily evident in the exploration
project area. The coastal belt offers deposit type optionality for copper
including porphyry and IOCG style deposits as well as newly recognised
intrusive-related copper and gold deposits.

 

Great Southern Copper is strategically positioned to support the global market
for copper - a critical battery metal in the clean energy transition around
the world. The Company is actively engaged in exploration and evaluation work
programmes targeting both large tonnage, low to medium grade Cu-Au as well as
high-grade Cu-Ag-Au deposits.

 

Further information on the Company is available on the Company's website:
https://gscplc.com (https://gscplc.com)

 

Competent Person Statement

 

The information in this announcement that relates to exploration results is
based on and fairly represents information reviewed or compiled by Mr Sam
Garrett, a Competent Person who is a Member of the Australian Institute of
Geoscientists and a Fellow of the Society of Economic Geologists. Mr Garrett
is the CEO and a shareholder of Great Southern Copper PLC. Mr Garrett has
sufficient experience that is relevant to the styles of mineralisation and
types of deposit under consideration and to the activity being 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". Mr Garrett has provided his prior written consent to the
inclusion in this announcement of the matters based on information in the form
and context in which it appears.

 

This announcement includes information that relates to Exploration Results
prepared and first disclosed under the JORC Code (2012) and extracted from the
Company's previous LSE announcements as noted, and the Company's Prospectus
dated 20 December 2021. Copies of these announcements are available from the
LSE Announcements page of the Company's website: www.gscplc.com
(http://www.gscplc.com) .

 

The Company confirms that it is not aware of any new information or data that
materially affects the information included within the Prospectus dated 20
December 2021.

 

Forward Looking and Cautionary Statements

Some statements in this announcement regarding estimates or future events are
forward-looking statements. They include indications of, and guidance on,
future earnings, cash flow, costs and financial performance. Forward-looking
statements include, but are not limited to, statements preceded by words such
as "planned", "expected", "projected", "estimated", "may", "scheduled",
"intends", "anticipates", "believes", "potential", "predict", "foresee",
"proposed", "aim", "target", "opportunity", "could", "nominal", "conceptual"
and similar expressions. Forward-looking statements, opinions and estimates
included in this report are based on assumptions and contingencies which are
subject to change without notice, as are statements about market and industry
trends, which are based on interpretations of current market conditions.
Forward-looking statements are provided as a general guide only and should not
be relied on as a guarantee of future performance. Forward-looking statements
may be affected by a range of variables that could cause actual results to
differ from estimated or anticipated results and may cause the Company's
actual performance and financial results in future periods to materially
differ from any projections of future performance or results expressed or
implied by such forward-looking statements. So, there can be no assurance that
actual outcomes will not materially differ from these forward-looking
statements.

 

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 (mailto:rns@lseg.com)
 or visit
www.rns.com (http://www.rns.com/)
.

RNS may use your IP address to confirm compliance with the terms and conditions, to analyse how you engage with the information contained in this communication, and to share such analysis on an anonymised basis with others as part of our commercial services. For further information about how RNS and the London Stock Exchange use the personal data you provide us, please see our
Privacy Policy (https://www.lseg.com/privacy-and-cookie-policy)
.   END  UPDGPUWUMUPAPPW