Oena Sales Results Q4 2025, Botswana and Corporate Update
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OENA SALES RESULTS Q4 2025, BOTSWANA AND CORPORATE UPDATE
VICTORIA, BRITISH COLUMBIA — 12 SEPTEMBER 2025 — Southstone Minerals Limited
(“Southstone” or the “Company”) (TSX.V – SML) reports Q4 2025 (June –August) diamond
production and sales results from its majority -owned Oena Diamond Mine in South Africa. The
Sandberg Section delivered strong operational performance with several high -value Special
diamonds sold. Through its 43% -owned subsidiary, African Star Minerals (Pty) Ltd, Southstone
has an agreement entitling it to 20% of gross diamond sales revenue (net of tender costs),
providing the Company with an 8.6% effective interest in sales while maintaining a lean operating
structure.
Q4 2025 Highlights (June–August 2025):
• 803.58 carats sold (+31% vs. Q3) from Sandberg Section
• Average price: USD $1,839/ct (+23% vs. Q3)
• Revenue: USD $1.48M (+61% vs. Q3)
• 8 Specials (>10.8 ct, avg. 19.7 ct): sold for USD $833,976, incl. 3 stones >USD $5,000/ct
(Photo 1)
• 14 Mid-size (5.3–9.6 ct): sold for USD $334,659
• Additional 124.50 carats produced in late August, incl. an 18.8 ct Special, to be sold in
September tender
In Q1 2026 (September to November 2025) mining will continue to exploit basal gravels at the
Sandberg Section.
Sandberg Section mining
period
Total
carats
sold
Total Number
of Diamonds
Average Diamond
Size (carats)
USD ($)
per carat
Total USD
Sales ($)
Sep 2018 to Nov 2021 2,690 1,157 2.33 NA NA
Nov 2023 to Aug 2024 769 319 2.41 1,935 1,488,052
Apr 2025 to Aug 2025 1,401 380 3.69 1,707 2,392,585
Table 1 – Sandberg Section 2018 to 2025 diamond sales.
Since acquiring Oena in 2014, the Company has sold 11,048 carats with an average stone size of
2.06 carats and an average price of USD $1,631 per carat, generating total sales of USD $18.0
million (Table 2).
Southstone Minerals Limited
2751 Graham Street
Victoria, British Columbia, V8T 3Z1
TSX Venture : SML
www.southstoneminerals.com
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Mining
period
Total
carats sold
Total Number
of Diamonds
Average Diamond
Size (carats)
USD ($)
per carat
Total USD
Sales ($)
Jul 2015 to Aug 2025 11,048 5,370 2.06 1,631 18,020,284
Table 2 – Oena Mine 2015 to 2025 diamond sales.
Southstone manages Oena directly, overseeing diamond sales, mining and contractor
consultation, licence reporting and site security. The Company maintains a management and
security team in South Africa, including the CEO of African Star and the Oena Site Manager. The
Executive Chairman, with external geological support, contributes technical and geological
oversight and ensures accurate internal reporting of operations.
Botswana Uranium Acquistion Update
Further to its news releases of February 18 and July 21, 2025, Southstone Minerals Limited
announces that it has entered a second addendum (the “Second Addendum”) to the binding term
sheet with Afrium Energy Pte. Ltd. (“Afrium”).
The Second Addendum, effective September 12, 2025, extends the End Date of the acquisition
agreement to March 12, 2026, to allow additional time for the renewal of the three prospecting
licences in the Republic of Botswana. All other terms of the agreement remain unchanged and in
full force.
Southstone recognizes that licence renewals in Botswana can be a lengthy administrative
process. The Company, together with Afrium, is actively working with the relevant authorities to
ensure the renewals are completed in due course. The Company remains committed to
advancing this strategic transaction while continuing to focus on its core operations at the Oena
Diamond Mine.
Corporate Update
The Company confirms it is not currently in compliance with Exchange Policy 3.1 and 3.2
requirements regarding the composition of the Board and appointment of officers but is acting
in good faith and continues to operate responsibly while working toward full compliance, which
will be restored upon closing of the Afrium transaction. At that time, the Company will:
• Appoint a Chief Financial Officer separate from the CEO; and
• Appoint at least one additional independent director, enabling the formation of a fully
compliant Audit Committee.
These appointments will bring the Company into compliance with TSX Venture Exchange
requirements.
The technical disclosure in this news release has been approved by Terry L. Tucker, P.Geo.,
Executive Chairman of the Company, and a Qualified Person as defined by National Instrument
43-101 of the Canadian Securities Administrators.
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ON BEHALF OF SOUTHSTONE MINERALS LIMITED
Terry L. Tucker, P.Geo.
Executive Chairman
For additional information, please contact Terry L. Tucker at [email protected]
Neither TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in
the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of
this release. Capitalized terms used herein that have not been defined have the same meanings
ascribed in the policies of the TSX.V.
Forward Looking Statements Disclaimer
Certain statements in this release are forward-looking statements, which are statements that are
not purely historical, including any statements regarding beliefs, plans, expectations, or
intentions regarding the future. Forward looking statements in this news release include
statements relating to the Company’s proposed production timeline, and the Company’s plans
for future production from the Oena Diamond Mine. Forward -looking statements are often
identified by terms such as “will”, “may”, “should”, “ant icipate”, “expects” and similar
expressions. All statements included in this news release, other than statements of historical fact,
are forward-looking statements that involve risks and uncertainties. There can be no assurance
that such statements will prove to be accurate and actual results, and future events could differ
materially from those anticipated in such statements. Important factors that could cause actual
results to differ materially from the Company’s expectations include quality and quantity of any
mineral deposits that may be located, the Company’s inability to obtain any necessary permits,
consents or authorizations required for its activities, the Company’s inability to raise the
necessary capital to be fully able to implement its business strategies, and other risks and
uncertainties disclosed in the Company’s latest interim Management Discussion and Analysis
filed with certain securities commissions in Canada.
The reader is cautioned that assumptions used in the preparation of any forward- looking
statements herein may prove to be incorrect. Events or circumstances may cause actual results
to differ materially from those predicted, as a result of numerous known a nd unknown risks,
uncertainties, and other factors, many of which are beyond the control of the Company. The
reader is cautioned not to place undue reliance on any forward- looking information. Such
information, although considered reasonable by management at the time of preparation, may
prove to be incorrect, and actual results may differ materially from those anticipated. Forward -
looking statements contained in this news release are expressly qualified by this cautionary
statement. The forward- looking statements contained in this news release are made as of the
date of this news release and the Company will update or revise publicly any of the included
forward-looking statements as expressly required by Canadian securities law.
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Photo 1 – Sandberg Special Size Diamonds sold in Q4 2025 (not to scale):
(1) 23.31 carats sold for USD $ 339,277 or USD $14,553 per carat.
(2) 47.15 carats sold for USD $161,161 or USD $3,418 per carat.
(3) 23.36 carats sold for USD $120,888 or USD $5,175 per carat.
(4) 10.91 carats sold for USD $54,583 or USD $5,003 per carat.
(5) 15.58 carats sold for USD $45,605 or USD $2,928 per carat.
(6) 11.24 carats sold for USD $44,241 or USD $3,936 per carat.
(7) 12.14 carats sold for USD $42,322 or USD $3,487 per carat.
(8) 13.32 carats sold for USD $25,900 or USD$1,944 per carat.