Rimfire's Managing - December 2023 Quarter - Activities Report

Commenting on the Quarterly Activities report, Rimfire's Managing Director Mr David Hutton said: 'Rimfire continues to explore for and discover the critical minerals that are associated with global decarbonisation strategies.

With the expansion of the Broken Hill Project, a successful capital raising, and funding commitments from GPR - our project partner at Avondale and Fifield, 2024 is shaping up to be a very busy and rewarding year for Rimfire and its shareholders. We look forward to commencing the scandium - focussed drilling programs at Murga and Melrose as well as commencing fieldwork on the newly acquired tenements at Broken Hill'

Introduction and Operational Summary

Rimfire Pacific Mining (ASX: RIM, 'Rimfire' or the 'Company') is an ASX-listed Critical Minerals exploration company which is advancing a portfolio of projects within the highly prospective Lachlan Orogen ('LO') and Broken Hill ('BH') districts of New South Wales. During the December 2023 Quarter (the 'Quarter'), Rimfire's exploration activities were focused on its 100% - owned Broken Hill Cobalt Project where a ground magnetic survey and a heritage assessment were undertaken to assist in planning for the next phase of exploration at the project. Subsequent to the Quarter, Rimfire substantially increased the size of the Broken Hill Cobalt Project with the acquisition of two Exploration Licences that lie adjacent to Rimfire's Bald Hill Cobalt Prospect from Castillo Copper Ltd (ASX: CCZ). The Castillo tenements are considered prospective for Bald Hill - style cobalt (+/- copper) sulphide mineralisation and bedrock - hosted Rare Earth Element (REE) mineralisation associated with shear - hosted pegmatite occurrences. The acquisition means that follow-up drilling at Bald Hill originally planned for the December 2023 Quarter has been deferred until the Company has completed a thorough review of the Castillo tenements and prioritised exploration targets across the expanded project area. At the time of writing, Rimfire was reviewing the results of the ground magnetic surveying and heritage assessment as well as negotiating land access agreements at Broken Hill to enable field reconnaissance and prospecting of the Castillo tenements. Additionally, a geochemical review of the Melrose Nickel Cobalt Scandium prospect (Avondale Earn In Project) during the December 2023 Quarter identified a new scandium search space (target) within unweathered serpentinised pyroxenite host rocks which lie beneath existing laterite - hosted mineralisation All exploration activities at the Fifield and Avondale Earn In Projects are funded by Rimfire's exploration partner - Golden Plains Resources (GPR) and during the March 2024 Quarter, Rimfire will ramp up exploration activities with aircore drilling (4,000 metres) planned for the Murga Scandium Prospect to be followed by a combined program of Reverse Circulation and Diamond drilling at the Melrose Cobalt Scandium Prospect. The Melrose drill program is still being designed but will be of sufficient detail to underpin the estimate of a maiden Mineral Resource Estimate (MRE) in accordance with the 2012 JORC Code for the prospect.

Also, during the March 2024 Quarter Rimfire expects to receive the final results of the Melrose metallurgical test work with 7 leaching tests (out of 8 planned tests) completed. The test work results will underpin the development of a conceptual processing flowsheet for optimising recoveries of a combined nickel - cobalt - scandium product from high-grade mineralised material at Melrose. Given that there have been no previous metallurgical studies of Melrose nickel - cobalt - scandium mineralisation, these results will build a strong foundation for further studies (if required) into commercialising the extraction of mineralised material from Melrose and other surrounding prospects.

Rimfire doubles Broken Hill Cobalt Project footprint

Immediately following the Quarter, Rimfire executed a Tenement Purchase Agreement with BHA No.1 Pty Ltd, a wholly owned subsidiary of Castillo Copper Ltd (ASX: CCZ), to acquire an unencumbered 100% of their Exploration Licences 8572 and 8599 ('Castillo tenements') which lie adjacent to Rimfire's Bald Hill Cobalt Prospect, 30 kilometres west of Broken Hill, NSW. Diamond drilling undertaken by Rimfire at Bald Hill last year successfully intersected high-grade cobalt (Co) associated with strongly disseminated to semi-massive sulphide (pyrite, pyrrhotite and trace chalcopyrite + sphalerite) mineralisation, including; 125m @ 0.13% Co from 198 metres in FI2470 including 97m @ 0.15% Co, 58m @ 0.13% Co from 62 metres in FI2471 including 2m @ 0.24% Co and 17m @ 0.15% Co, 33m @ 0.11% Co from 58 metres in FI2469 including 4m @ 0.23% Co and 2m @ 0.21% Co, and 100m @ 0.08% Co from 71 metres in FI2470 including 68m @ 0.10% Co.

The Castillo tenements cover the same sequence of Proterozoic age deformed and metamorphosed gneiss, psammite, and amphibolite units that host the Bald Hill cobalt sulphide mineralisation. An examination of the NSW Government Minview online GIS portal reveals several historic mineral occurrences that require follow up to better determine their geological significance and exploration potential. Of initial interest are a cluster of gossanous, quartz veined and copper-stained occurrences within the northwestern portion of EL8572 (NSW Mineral Occurrences 181678, 181681, 181683 -181684, 181686, and 181688) and multiple shear - hosted davidite - bearing pegmatite occurrences within the southern portion of EL8572 and EL8599 (NSW Mineral Occurrences 181344 - 181348). Davidite is a rare earth oxide mineral with chemical end members of either Lanthanum or Cerium

Other 100% - owned projects Following the September 2023

Quarter acquisition of the Porters Mount Project, which adjoins Rimfire's 100% - owned Cowal Copper Gold Project (Lachlan Orogen), the Company has carried out a detailed technical review of the expanded project area during the December 2023 Quarter and is currently prioritising targets for follow up. Other than ongoing desktop review, no field work was undertaken during the December 2023 Quarter on the 100% - owned Valley Copper Project which also lies within the Lachlan Orogen of New South Wales. Drilling undertaken by Rimfire at the Valley demonstrated that the project contains similar rock types to the host rocks of the Northparkes Copper Gold Mine which is located 34 kilometres east of the Valley. Northparkes has total Measured and Indicated Resources (as at 31 December 2019) of 356Mt @ 0.55% copper, 0.20g.t gold (1.96Mt copper and 2.33Moz gold - refer to Northparkes website). Evolution Mining (ASX: EVN) recently purchased an 80% interest in the mine for up to US$475M (see Evolution Mining's ASX Announcement dated 5 December 2023).

Forward looking statements Disclaimer

This document contains 'forward looking statements' as defined or implied in common law and within the meaning of the Corporations Law. Such forward-looking statements may include, without limitation, (1) estimates of future capital expenditure; (2) estimates of future cash costs; (3) statements regarding future exploration results and goals. Where the Company or any of its officers or Directors or representatives expresses an expectation or belief as to future events or results, such expectation or belief is expressed in good faith and the Company or its officers or Directors or representatives, believe to have a reasonable basis for implying such an expectation or belief. However, forward-looking statements are subject to risks, uncertainties, and other factors, which could cause actual results to differ materially from future results expressed, projected, or implied by such forward looking statements. Such risks include, but are not limited to, commodity price fluctuation, currency fluctuation, political and operational risks, governmental regulations and judicial outcomes, financial markets, and availability of key personnel. The Company does not undertake any obligation to publicly release revisions to any 'forward looking statement'.

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Competent Persons

Declaration The information in the report that relates to Exploration and Resource Results is based on information reviewed and/or compiled by David Hutton who is a Competent Person and is a Fellow of The Australasian Institute of Mining and Metallurgy. Mr Hutton has over 30 years' experience in the minerals industry and is the Managing Director and CEO of Rimfire Pacific Mining. Mr Hutton has sufficient experience that is relevant to the style of mineralisation and type of deposits under consideration and to the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the 'Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves'. Mr Hutton consents to the inclusion of the matters based on the information in the form and context in which it appears.

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