Diatreme Resources Limited continued to expand its high-grade silica sand resource in Far North Queensland, with the Company's Si2 resource estimate soaring by 89% to 235 million tonnes (Mt), up from 124.1Mt previously. Diatreme's total silica sand resource base now exceeds 310Mt across its high-grade silica projects. Located within the Northern Silica Project (NSP area) of Diatreme's Cape Bedford (EPM17795) exploration tenement, Si2 now represents the major project within the Company's existing silica sand resources, exceeding the estimated 75.5Mt resource of the Company's Galalar Silica Sand Project (GSSP).

Diatreme's expanding resource base is highly strategic given its location in a stable and ESG compliant jurisdiction and amid increasing demand growth from Asia's booming solar PV industry. The expanded Mineral Resource was estimated by independent experts Ausrocks Pty Ltd. The additional resources confirm the target Si2 dune system has the potential to host significant silica sand resources, as incremental exploration has increased the resource size significantly. Diatreme's intention is to progress to Scoping Studies to determine the potential economics of establishing a silica sand operation at Si2.

This will potentially facilitate the "fast tracking" of a second independent major high purity silica operation, with the Northern Silica Project benefitting from its proximity to the existing State-owned Cape Flattery Port, owned by Ports North. Inferred & Indicated Resources A third drilling program was undertaken in late 2022, with a total of 1,848.7m comprising 76 aircore drill holes, 12 hand auger holes, and 19 vacuum holes (from 2021 exploration in PLT). These were utilised to upgrade the existing Si2 resource, in accordance with the JORC Code (2012).

The mineral resource estimate is built upon 3,783.3m of various drilling methods across 188 drill holes. 2023 Project Development Diatreme is targeting the following next steps for the NSP, including the Si2 resource: Continued exploration and project development throughout 2023, focussed on the Si2 dune complex located within and around the Northern Silica Project, adjacent to the CFSM operations. Finalising a Scoping Study to determine the economics and potential development of the area.

This will be focused on the Si2 resource and include additional investigation of solutions on infrastructure and export leveraged to the Cape Flattery Port. Bulk sample metallurgical test work to continue on the Si2 project, to determine its amenability to processing utilising Diatreme's Galalar optimised silica product processing criteria. This targets assessment and delivery of a high value low iron, high purity silica product.

Environmental monitoring and studies within the framework of the EIAS studies for the ML100308 Northern Silica Application process. Diatreme continues to advance discussions and negotiations regarding establishment of a mining project agreement for the northern silica project with Hopevale Congress Aboriginal Corporation (RNTBC), Walmbaar Aboriginal Corporation (RNTBC) affected native title holders and the broader Hopevale community.