Investor Presentaiton

Resources & Reserves Metric Li B Tonnes Grade Grade Equivalent Grade Equivalent Contained Tonnes Li₂CO3 H₂BO3 Li₂CO3 H₂BO3 (mt) (ppm) (ppm) (%) (%) (kt) (kt) Mineral Resource Measured Resource 39.0 1,700 14,550 0.9 8.3 360 3,240 Indicated Resource 88.0 1,550 14,150 0.8 8.1 730 7,110 Measured and Indicated Resource 127.0 1,600 14,270 0.8 8.2 1,090 10,350 Inferred Resource 19.5 1,600 13,800 0.9 7.9 170 1,530 Total Mineral Resource 146.5 1,600 14,200 0.9 8.1 1,250 11,890 Ore Reserve Proved Reserve 29.0 1,900 16,250 1.0 9.3 290 2,700 Probable Reserve 31.5 1,700 14,650 0.9 8.4 280 2,620 Total Proved and Probable Ore Reserve 60.0 1,800 15,400 1.0 8.8 580 5,310 • Approximately half of the Ore Reserve is classified as Proved Ore Reserve provides 94% of tonnes in current 26-year mine plan Total Mineral Resource of 146.5 mt containing a total of 1.2 mt of lithium carbonate and 11.9 mt of boric acid ioneer Source: For further information on Resources and Reserves see ASX release titled Rhyolite Ridge Ore Reserve Increased 280% to 60 million tonnes dated 30 April 2020. Note, totals may differ due to rounding. Mineral Resources include Ore Reserves. ioneer Investor Presentation ASX: INR www.ioneer.com 27

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