Announcement PDF 1 May 2024 Greenstone Shareholders to vote on Horizon Merger Horizon Minerals Limited (ASX: HRZ) (Horizon) and Greenstone Resources Limited (ASX: GSR) (Greenstone) refer to the announcements on 13 February 2024 and 2 April 2024 in relation to the proposed merger between Horizon and Greenstone to be conducted by way of schemes of arrangement under the Corporations Act 2001 (Cth), whereby Horizon will acquire 100% of the fully paid ordinary shares in Greenstone (Share Scheme) and 100% of the listed Greenstone options (Option Scheme, and together with the Share Scheme, the Schemes), subject to the satisfaction of various conditions. COURT ORDERS CONVENING THE SCHEME MEETING On 30 April 2024, the Supreme Court of Western Australia made orders: • directing Greenstone to convene a meeting of Greenstone shareholders for the purpose of considering and to vote on the Share Scheme (Share Scheme Meeting); • directing Greenstone to convene a meeting of Greenstone listed optionholders for the purpose of considering and to vote on the Option Scheme (Option Scheme Meeting); and • approving the despatch of an explanatory statement providing information about the Schemes together with the notices of the Share Scheme Meeting and Option Scheme Meeting (the Scheme Booklet) to Greenstone shareholders and listed optionholders. SHARE SCHEME MEETING The Share Scheme Meeting, at which Greenstone shareholders will vote on the proposed Share Scheme, is scheduled to take place at 12:00pm (AWST) on Friday, 31 May 2024 and will be held at the registered offices of Greenstone, Level 2, 16 Ord Street, West Perth, WA 6005, and virtually via an online platform powered by Greenstone’s share registry, Automic. Greenstone shareholders and their proxies, attorneys or corporate representatives will be able to attend the Share Scheme Meeting in person or participate in the Share Scheme Meeting via the virtual platform. Greenstone strongly encourages Greenstone shareholders to lodge a directed proxy in the event that they are not able to attend the Share Scheme Meeting. All Greenstone shareholders entered on the Greenstone share register as holders of Greenstone shares at 5:00pm (AWST) on Wednesday, 29 May 2024, will be eligible to vote at the Share Scheme Meeting. Further information on how to participate and vote at the Share Scheme Meeting is set out in the Scheme Booklet. Horizon Minerals Limited | Greenstone Resources Limited | ASX Announcement 1 ASX ANNOUNCEMENT OPTION SCHEME MEETING The Option Scheme Meeting, at which Greenstone optionholders will vote on the proposed Option Scheme, is scheduled to take place at 1:00pm (AWST) on Friday, 31 May 2024 and will be held at the registered offices of Greenstone, Level 2, 16 Ord Street, West Perth, WA 6005, and virtually via an online platform powered by Greenstone’s share registry, Automic. Greenstone optionholders and their proxies, attorneys or corporate representatives will be able to attend the Option Scheme Meeting in person or participate in the Option Scheme Meeting via the virtual platform. Greenstone strongly encourages Greenstone optionholders to lodge a directed proxy in the event that they are not able to attend the Option Scheme Meeting. All Greenstone optionholders entered on the Greenstone register of listed options as holders of Greenstone listed options at 5:00pm (AWST) on Wednesday, 29 May 2024, will be eligible to vote at the Option Scheme Meeting. Further information on how to participate and vote at the Option Scheme Meeting is set out in the Scheme Booklet. SCHEME BOOKLET TO BE DESPATCHED SHORTLY The Scheme Booklet, including the notice of the Share Scheme Meeting and notice of Option Scheme Meeting as well as an Independent Expert’s Report, is expected to be sent to Greenstone shareholders on or around 1 May 2024, following registration of the Scheme Booklet by the Australian Securities and Investments Commission (ASIC). A further announcement to the ASX attaching the Scheme Booklet will be made by Greenstone and Horizon following the registration of the Scheme Booklet by ASIC. Greenstone shareholders and listed optionholders should carefully read the Scheme Booklet in its entirety, including the materials accompanying it, before deciding whether to vote in favour of the Share Scheme and Option Scheme, as applicable. This announcement has been approved for release by the Board of Directors of Horizon Minerals Ltd and Greenstone Resources Ltd. For further information, please contact: Grant Haywood Horizon CEO Tel: +61 8 9386 9534 grant.haywood@horizonminerals.com.au Michael Vaughan Media Relations – Fivemark Partners Tel: +61 422 602 720 michael.vaughan@fivemark.com.au Horizon Minerals Limited | Greenstone Resources Limited | ASX Announcement 2 ASX ANNOUNCEMENT ⚫ MARCH 2024 Chris Hansen Greenstone MD & CEO Tel: +61 8 9481 3911 chris.hansen@greenstoneresources.com.au Horizon Minerals Limited | ASX Announcement 3