Kore Potash plc, the potash development company with 97%-ownership of the Kola and DX Potash Projects in the Sintoukola Basin, located within the Republic of Congo (“RoC”), is pleased to provide a progress update on the Dougou Extension Project (“DX”) Definitive Feasibility Study (“DFS”) Phase 1. A summary of the progress is presented herein.

Highlights

• Phase 1 of the definitive feasibility study remains on track to be completed in May 2021
• The drilling campaign is progressing on schedule. Mud rotary drilling of drill holes DX 10 and DX 11 has been completed to the anhydrite layer and the holes have been cased and grouted ready for diamond drilling of core
• Geo-mechanical testing of samples from previously drilled core has commenced with unconfined compressive strength (“UCS”) and triaxial compressive strength (“TCS”) tests in the Agapito Associates Inc. (“AAI”) laboratory in the United States of America and creep tests at the Institut fur Gebirgsmechanik (“IFG”) laboratory in Germany
• The planned dissolution test work has been completed at AAI’s laboratory in the United States of America.
• The dissolution test results indicate that production brine can be produced with KCl concentrations in the range of 170-200 g/l which creates potential to improve on the 165g/l determined in the Pre-Feasibility Study (“PFS”).
• Further work is now planned to determine the optimum residence time/ production brine grade to maximise economic return
• This information will be used to create an updated brine model to predict production of KCl from the caverns over the life of mine

Brad Sampson, CEO of Kore, commented:

“The work programme in Phase 1 of the DX Definitive Feasibility study is focused on improving our knowledge of a number of the key drivers for the success of this project.”

“We are pleased that the programme is progressing on schedule and look forward to being able to report the full results of this work and the expected positive impact on the project economics.”

“The DX project stands out as a very low cost producer of MoP, with compelling economics and close proximity to port and to our target markets, the more work we do, the more convinced we are that this is potentially one of the world’s very best potash assets.”

DX Definitive Feasibility Study Phase 1 update

The work programme including the planned diamond drilling campaign for the First phase of the DX DFS remains on track for completion in May 2021 and within budget.

Drilling programme

The mud rotary drilling of drill hole DX 10 has been completed to the anhydrite layer which directly overlays the salt layers hosting the potash deposit. This drill hole has been cased and grouted ready for diamond drilling of core. The anhydrite level was at 338m below natural ground level.

The mud rotary drilling of DX 11 has been completed to the anhydrite layer and cased and grouted. The anhydrite level was at 364m below natural ground. The diamond drill rig has been positioned over drill hole DX 11 and diamond coring of the salt and potash layers has commenced.

Mud rotary drilling of the upper part of drill hole DX 12 is planned to commence before the end of November.

Positions of Dx 10, 11 and 12 are shown on Figure 1.

Geo-mechanical testing

19 of the 24 unconfined compressive strength (UCS) tests have been completed on samples of core from holes previously drilled at DX.

The 19 samples provided for UCS testing included 5 from the halite salt back overlying the potash seams, 4 from the top seam sylvinite (TSS), 3 from the halite interbed, 5 from the hanging wall seam sylvinite (HWSS) and 2 from the halite below the HWSS.

It is planned to deliver additional samples representing 3 anhydrite layer samples from the current drilling program and 1 additional TSS and 1 additional sample from the halite below the HWSS from existing samples taken from the previous drilling program.

Preparation of samples for the triaxial compressive strength (TCS) tests have commenced on 22 samples. The DX core samples provided included 1 from the anhydrite layer, 3 from the halite salt back, 6 from the TSSS, 3 from the halite interbed, 6 from HWSSS and 3 from the halite below HWSS.

Creep tests have commenced at the IFG laboratory in Germany, with 6 core samples being tested currently and another 6 planned for testing commencing in late December.

Dissolution test work

Selective dissolution testing was conducted on 36 quarter-core samples, acquired from the DX Potash Project site, in AAI’s laboratory in Grand Junction, Colorado. The test results are shown in the Table in Appendix A.

The positions of the holes from where the samples were taken for dissolution test work are shown in Figure 1.

Figure 1. Map of the DX deposit area showing the positions of drill-holes

(available at www.korepotash.com)

Dissolution testing was performed at a temperature of 90°C, with pre-concentrated solvents of 170, 180, 190, and 200g/l KCl and saturated NaCl. These tests generated data to improve understanding of the relationship between dissolution rate and KCl concentration. Understanding this relationship is important to support the prediction of expected brine concentrations during commercial solution-mining operations. The dissolution test results are shown in the Table in Appendix A.

The dissolution test results for the DX potash samples indicated that the dissolution rates with high solvent concentrations (170-200 g/l) are lower than the dissolution rates observed during the 2019 testing program with lower solvent concentrations (100-160 g/l). These results suggest that the optimal production brine concentration will be in the range of 160-180 g/l KCl.

The dissolution test results showed consistent dissolution rates when the solvent KCl concentration was high (170-200 g/l). This suggests that brine can be produced with KCl concentrations in the range of, or even higher than, 170-200 g/l. Kore’s consultants have indicated that these results are in line with other potash operations and indicate the previous PFS assumption for production brine concentration of 165 g/l KCl was reasonable. The final optimal production brine concentration will be an outcome of the cavern brine grade model in Phase 1.

An updated cavern brine grade model, incorporating the results of this test work is planned for development as part of this Phase 1 of the DFS. Production brine KCl concentration will be balanced with the required cavern residence time for optimal project economics.

The updated brine model will become the basis for the updated production plan in the DFS.