Adrian Day

Mohamed Sidibe

David Kranzler

Don DeMarco

Eric Winmill

Tony Christ

John Pereira

- **Fortuna Mining Corp.** has entered into a binding Heads of Agreement with **DeSoto Resources Limited** to establish an exploration alliance and joint venture in Guinea's Siguiri Basin.  **[1341335_0001104659-25-095939_tm2527852d1_ex99-1.htm:0]** 
- The alliance is focused on identifying "Go Projects" with the potential to host multi-million-ounce gold deposits.  **[1341335_0001104659-25-095939_tm2527852d1_ex99-1.htm:0]** 
- In the joint venture phase for "Go Projects," Fortuna will hold a **70 percent** interest, with DeSoto holding **30 percent**.  **[1341335_0001104659-25-095939_tm2527852d1_ex99-1.htm:0]** 
- Fortuna will solely fund exploration for these projects until the later of **three years** or **US$12.5 million** in cumulative expenditure.  **[1341335_0001104659-25-095939_tm2527852d1_ex99-1.htm:0]**

FORTUNA MINING (FSM)