SOUTHSTONE REPORTS PARTIAL Q3 2026 DIAMOND SALES RESULTS

Southstone Minerals Limited has delivered impressive diamond sales results from the first two tenders of fiscal Q3 2026 at its Oena Diamond Mine in South Africa. The company reported gross diamond sales of US$2,078,798 from 1,043 carats sold at an average price of US$1,993 per carat across Tenders 275 and 276 held in March and April 2026. The March 19 tender alone generated US$1,196,470, marking the second-highest single-month performance since Southstone acquired the Oena mine in 2014.

The standout feature of these sales was the exceptional performance of special size diamonds larger than 10.8 carats. Fifteen such stones, averaging 17 carats each, commanded US$1,301,625 in combined proceeds, representing 63% of total gross sales value despite comprising a small fraction of the total carat count. This demonstrates the mine's continued ability to produce high-value, large diamonds that drive outsized returns. The achieved price of US$1,993 per carat was only marginally below the US$2,027 per carat average realized since January 2024, indicating stable pricing in the current market environment.

Operationally, mining continues at the Sandberg S7 Basal section, which has proven to be a prolific source of quality diamonds since operations resumed in April 2025. The section has now produced 4,732 carats across 1,633 diamonds since April 2025, generating over US$10 million in gross sales at an average price exceeding US$2,100 per carat. The company maintains 590 carats in unsold inventory, including eight special diamonds averaging 15.30 carats each, which are scheduled for sale at the May 21, 2026 tender.

Southstone operates under a revenue-sharing agreement where gross sales exceeding ZAR 10 million trigger an 80:20 split between Rietput Delwery BK and African Star Minerals, giving Southstone an effective 8.60% economic interest in the operation. Both Q3 tenders exceeded this threshold, ensuring the company benefits from the higher revenue split. The consistent production of large, high-value diamonds from the Sandberg section positions Southstone well for continued strong performance, particularly given the premium pricing that special size diamonds command in the current market.