Mr. Jonathan Hamel reports

MOSAIC CLOSES A FIRST TRANCHE OF A PRIVATE PLACEMENT AND PREPARES TO DRILL ON GOLDEN ISLAND

Mosaic Minerals Corp. has closed an initial tranche of a private placement of units and flow-through units, as well as the imminent launch of its first drilling campaign on the Golden Island gold project in Abitibi, Que.

Private placement

The company announces the closing of a first tranche of a private placement comprising 3,526,190 flow-through units at 1.05 cents per FT unit and 2,609,191 units at 8.5 cents per unit, for aggregate gross proceeds of $592,031.

Each FT unit consists of one common share of the company to be issued as a flow-through share within the meaning of the Income Tax Act (Canada) and one common share purchase warrant. Each warrant entitles the holder to purchase one common share at a price of 17 cents for a period of 12 months from the date of issuance.

Each unit consists of one common share of the company and one common share purchase warrant. Each warrant entitles the holder to purchase one common share at a price of 12 cents for a period of 24 months from the date of issuance.

The gross proceeds from the sale of the FT units will be used by the company to incur eligible Canadian exploration expenses on the Golden Island project that qualify as flow-through mining expenditures, as such terms are defined in the Income Tax Act (Canada), in connection with the company's projects in Quebec, Canada. All eligible expenditures will be renounced in favour of the subscribers of the FT units, effective Dec. 31, 2026.

In connection with the offering, the company paid an 8-per-cent cash finder's fee (totalling $20,160) and issued a total of 192,000 finders' warrants to two arm's-length finders. Each finder's warrant is exercisable to acquire one additional common share at a price of 8.5 cents per warrant for a period of 24 months from the date of issuance.

All securities issued in connection with the offering will be subject to a hold period of four months and one day, ending on Jan. 22, 2027. The offering is subject to final approval by the Canadian Securities Exchange (CSE).

Technical fieldwork and drilling program

As stated in its press release dated Aug. 25, 2026, the company has completed a program of technical work and field exploration to prepare for the initial drilling campaign. Key highlights include:

• Discovery of new gold-bearing zones in the southwest extension of the main showing;
• Recurring presence of visible gold observed in multiple channel samples;
• Confirmation of a complex structural network comprising shear veins, extension/tension veins and stockwork-style networks, hosted within a mineralized granodiorite matrix spanning several tens of metres in width;
• A major geophysical corridor exceeding one kilometre in length, featuring a high-amplitude magnetic anomaly and a VLF electromagnetic conductor -- a feature historically validated by a drill hole that intersected 1.13 grams per tonne Au over 5.60 metres;
• Over 340 channel samples collected and sent for analysis.

The company expects to receive all results from the collected samples within the coming weeks.

This successfully completed work program paves the way for a fully financed initial drilling campaign of at least 2,500 metres. The company intends to test the area near historical drill holes completed by SOQUEM in 1982, as well as the new gold-bearing zone discovered during the technical work carried out in the summer of 2026.

"We are excited about the potential of the Golden Island property in light of the technical work conducted in the summer of 2026. The initial drilling campaign is essential at the current stage of development. We aim to launch it as soon as possible to take advantage of the autumn season. We are initially targeting a 10-hole campaign with a minimum depth of 250 metres per hole, for a total of 2,500 metres," stated Jonathan Hamel, president and chief executive officer of Mosaic.

Qualified person

The scientific and technical information of Mosaic Minerals included in this press release has been reviewed and approved by Robert Gagnon, PGeo, director of Mosaic Minerals and qualified person under National Instrument 43-101 respecting information concerning mining projects.

About Mosaic Minerals Corp.

Mosaic Minerals is a Canadian mining exploration company listed on the Canadian Securities Exchange (CSE: MOC). The company is developing the Golden Island (Au), Amanda (Au), and Gaboury (Ni) projects located in Abitibi and James Bay (Quebec).

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