Southstone Minerals sells 2,132.33 carats in fiscal Q3

Mr. Terry Tucker reports SOUTHSTONE REPORTS Q3 2026 DIAMOND SALES RESULTS AND APPOINTMENT OF INDEPENDENT DIRECTOR AND CHIEF FINANCIAL OFFICER Southstone Minerals Ltd. has released diamond sales results from the Oena diamond mine in South Africa for fiscal Q3 2026 (March to May, 2026), provided an operational update on production at the Oena diamond mine, and provided an update on the company's regulatory and corporate matters. Q3 2026 diamond sales The company sold diamonds at three tenders during Q3 2026 -- tenders 275, 276 and 277. Aggregate Q3 2026 gross diamond sales were $4,733,181 (U.S.) from 2,132.33 carats sold across 723 diamonds at an average price of $2,220 (U.S.) per carat. Each tender exceeded the 10-million-South-African-rand gross sales threshold in the contract mining and diamond recovery agreement between African Star Minerals Pty. Ltd. and Rietput Delwery BK, and the 80/20 Rietput/African Star revenue split (net of tender costs) applied to each tender. Southstone's effective economic interest in net tender proceeds is 8.60 per cent. Tender 277 delivered 17 single-stone special diamonds (greater than 10.8 carats) totalling 273.12 carats, with combined proceeds of $1,663,238 (U.S.). The two largest stones were a 27.019-carat diamond, which sold for $248,248 (U.S.) and a 26.421-carat diamond, which sold for $145,541 (U.S.). Tender 277 also included an 8.233-carat fancy yellow diamond, which sold for $178,778 (U.S.), equating to $21,715 (U.S.) per carat -- the highest U.S. dollars per carat realized at the Oena diamond mine since the company commenced production in 2015. Across Q3 2026, the company sold 32 special diamonds for combined proceeds of $2,964,863 (U.S.), representing approximately 63 per cent of Q3 2026 gross sales value. Since the company's acquisition of Oena in 2015, cumulative gross diamond sales from the Oena diamond mine total $28,370,761 (U.S.) from 15,464 carats sold across 6,729 diamonds at an average price of $1,835 (U.S.) per carat. Subsequent to Tender 277, production sorts on May 24 and May 25, 2026, at the Sandberg S7 Basal section recovered an additional 434.55 carats, including nine special diamonds (greater than 10.8 carats) totalling 229.05 carats pending sale at the first tender of fiscal Q4 2026. Operational update -- Oena diamond mine Stripping for new pit: Mining at the Sandberg S7 Basal section of the Oena diamond mine, from which Q3 2026 production was derived, is approaching the limit of the current pit. The contract miner has advised that approximately six to eight weeks of overburden stripping will be required to open a new pit along strike before mining and recovery can resume in that area. During the stripping period, diamond recoveries are expected to be reduced. Corporate update CC Mining Ltd. loan: On May 22, 2026, Southstone remitted the final payment of $55,350.24 (U.S.) to CC Mining under the loan agreement dated Jan. 29, 2024, between the company (as borrower) and CC Mining (as lender). The final payment comprised $54,569.15 (U.S.) of principal and $781.09 (U.S.) of interest accrued at SOFR (secured overnight financing rate) plus a margin of 8.00 per cent per annum on an actual/365-day basis. Following this payment, all principal and interest under the loan agreement have been repaid and the loan agreement is to be discharged in accordance with its terms. Director appointment and audit committee: Effective May 25, 2026, Kevin Ma was appointed to the board of directors of the company as an independent director and chair of the audit committee. The board of directors has determined that Mr. Ma is independent of the company and of the management of the company within the meaning of National Instrument 52-110, Audit Committees, having considered all of his existing and recent relationships with the company and concluded that none of them constitutes a material relationship that could reasonably be expected to interfere with the exercise of his independent judgment as a director. Mr. Ma is not an officer or employee of the company or of any of the company's subsidiaries or affiliates; does not own or control, directly or indirectly, securities of the company carrying more than 10 per cent of the votes attached to the company's outstanding voting securities; and does not receive, directly or indirectly, any consulting, advisory or other compensatory fee from the company other than in his capacity as a director and chair of the audit committee. Mr. Ma is a chartered professional accountant (CPA, CA) and the principal of Calibre Capital Partners Corp., a Vancouver-based corporate finance advisory firm that advises public and private companies on governance and capital markets strategies. He concurrently serves as executive vice-president, chief financial officer and a director of Kalo Gold Corp. and has held officer and director positions at a number of other publicly listed companies, with practical experience of TSX Venture Exchange requirements and continuous-disclosure obligations. Mr. Ma holds a bachelor of arts and a diploma in accounting from the University of British Columbia. Following the appointment, the board of directors of the company comprises Terry L. Tucker, Donna M. Moroney, Neil Budd and Mr. Ma, and the audit committee comprises Mr. Ma (chair), Mr. Budd and Ms. Moroney. Chief financial officer appointment: Effective May 25, 2026, Derek Sobel of Catapult Consulting Corp. was appointed as chief financial officer of the company. Mr. Sobel has 15 years of experience in financial reporting, corporate modelling and financial audits, working with public and private companies primarily in the mining, resource and technology industries. Mr. Sobel has held chief financial officer positions at a number of Canadian public companies and has been instrumental in their growth by building out robust financial reporting processes, implementing internal controls, developing internal budgeting and forecasting models, and streamlining day-to-day accounting processes. Mr. Sobel is a chartered professional accountant (CPA, CA) and holds a bachelor of commerce from the University of Alberta. The May 25, 2026, appointments of Mr. Sobel as chief financial officer (separate from the chief executive officer) and Mr. Ma as an independent director and chair of the audit committee together address the deficiencies identified by the TSX-V in its notice to the company dated May 15, 2025 (submission No. 700966), under TSX-V Policy 3.1 Paragraph 5.7 (at least two independent directors), Paragraph 5.8 and Paragraph 5.9 (separation of CEO and CFO), and Paragraph 21(b) (audit committee composition), subject to the filing of an electronic personal information form and electronic declaration on the TMX Portal for each of Mr. Ma and Mr. Sobel as new insiders, which the company expects to complete promptly. Qualified person statement The technical disclosure in this news release relating to diamond production, recovery and sales has been approved by Terry L. Tucker, PGeo (APEGBC), executive chairman and a qualified person as defined by National Instrument 43-101. Mr. Tucker has verified the production and sales records disclosed in this release. We seek Safe Harbor.