Endeavor DEVELOPMENT Cobar, Australia OPERATOR Polymetals Resources Ltd. ("Polymetals") COMMODITY TYPE TERMS LAND AREA Zinc, Silver, Lead Royalty 4.0% NSR 109,919 ha Royalty Summary Reserves Endeavor is a past-producing major underground silver-zinc-lead Reserves & Resources - Zn mine in Cobar, Australia owned by Polymetals Resources Limited. P&P Reserves (mlbs Zn) 499 Endeavor commenced production in 1982 and produced more than M&I Resources (mlbs Zn) 2,338 32 million tonnes of ore at 8.01% zinc and 89.2 g/t silver. The mine Inferred Resources (mlbs Zn) 526 was placed on care and maintenance in 2019. Reserves & Resources - Pb P&P Reserves (mlbs Pb) 221 On October 16 2023, Polymetals released a postive Endeavor Mine M&I Resources (mlbs Pb) 1,387 Inferred Resources (mlbs Pb) 253 restart study outlining potential for a robust and pro昀椀table future plan for the mine. As part of the restart plan Polymetals projects an ini- Reserves & Resources - Ag tial 10-year mine life producing 9.8 Moz silver, 210 kt zinc and 62 P&P Reserves (koz Ag) 14,059 M&I Resources (koz Ag) 34,697 kt lead with 昀椀rst concentrate production targeted for H2-2024. The Inferred Resources (koz Ag) 7,783 mine restart study produced a NPV8% of A$201 million and an IRR of 91%, with expenditures estimated to be A$23.8 million. Concurrent Metalla Royalty Ounces - GEOs with development of the mine, Polymetals continues to explore and P&P Reserves (koz) 21.7 delineate additional Mineral Resources near the main ore body. M&I Resources (koz) 92.5 Inferred Resources (koz) 19.7 Metalla holds a 4.0% NSR royalty on all silver, zinc, and lead pro- * Mineral Resources are reported inclusive of Mineral Reserves * For royalty ounce calculation, Metalla estimates 100% of the Endeavor Mineral Resources and Mineral duced from Endeavor. Reserves are subject to our royalty interest and the zinc and lead Royalty GEOs (factor in a 15% NSR smelting charge). Zinc has been converted to Royalty GEOs assuming $1.10 per pound. Lead has been converted to Royalty GEOs assuming $1.00 per/oz. Silver has been converted to Royalty GEOs assuming $23.00/oz. Royalty & Mineralization Map 20 Metalla Royalty & Streaming Ltd.