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ioneer QUARTERLY ACTIVITIES REPORT for the period ending 30 September 2021 Highlights • Sibanye - Stillwater to make US $ 490M strategic investment in Rhyolite Ridge , substantially funding the Project . Investment underpins Rhyolite Ridge's quality and future as a major lithium and boron producer in the US . ioneer and Sibanye - Stillwater JV to secure debt financing to ensure the Project is fully funded to production . Sibanye - Stillwater to subscribe for a strategic placement of US $ 70M in ioneer ordinary shares . • Rhyolite Ridge awarded key air and water permits necessary to commence construction . Key engineering contracts awarded to FLSmidth , Veolia and DuPont Clean Technologies . Wednesday , 20 October 2021 - ioneer Ltd ( ioneer or the Company ) ( ASX : INR ) , an emerging American lithium – boron supplier , is pleased to report on its activities for the quarter ending 30 September 2021 and to provide an update on the development of its 100 % -owned Rhyolite Ridge Lithium - Boron Project ( Rhyolite Ridge or the Project ) in Nevada , USA . ioneer Managing Director , Bernard Rowe said : " The signing of a strategic partnership with Sibanye - Stillwater is the most significant milestone in the history of ioneer . The partnership will provide the majority of funding to bring Rhyolite Ridge into operation and is a testament to the importance of this Project in supplying critically needed lithium chemicals into US supply chains . Sibanye - Stillwater is a strong strategic partner with a proven track record of developing and operating major mining projects around the world , including the United States . We share Sibanye - Stillwater's strong ESG credentials , and we will draw on its expertise to ensure Rhyolite Ridge is at the very forefront of sustainable production and operation . " The quarter saw significant progress towards commencement of construction of Rhyolite Ridge . We have now been awarded the air and water permits necessary for Project approval . The awarding of the Water Pollution Control Permit during the quarter means we now have two of the three critical permits required for construction . We are continuing to correspond with relevant US regulators on the publication of the Notice of Intent , which will lead to a Record of Decision for an approved Plan of Operation , which is the final approval for the Project . " " We also signed three material engineering contracts in the period , with international partners , FLSmidth , Veolia and DuPont Clean Technologies , which have all commenced design and engineering work on the Project . " As the most advanced lithium development project in the US , ioneer is in a strong position to capitalise on the increased demand for lithium products in line with the US Government's efforts to secure critical minerals supply chains for end uses like EVs and renewable energy infrastructure in the US . There was a noticeable uptick in inbound enquires from potential offtake parties this quarter , and the Company is assessing multiple lithium supply opportunities . " ioneer Ltd. ( ASX : INR ) Suite 5.03 , 140 Arthur Street , North Sydney , NSW 2060 T : +61 2 9922 5800 W : ioneer.com ABN : 76 098 564 606