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Riverside Resources Announces Completion of Phase One Drilling at Union Project and Now Awaits Drill Assay Results ~Over 1600 metres drilled to date and 700+ samples shipped to laboratory~

Drill Results

Riverside Resources Announces Completion

of Phase One Drilling at Union Project and

Now Awaits Drill Assay Results

~Over

1600 metres drilled to date and 700+ samples shipped to laboratory~

Vancouver, British Columbia--(Newsfile Corp. - November 12, 2025) - Riverside Resources Inc. (TSXV:

RRI) (OTCQB: RVSDF) (FSE: 5YY0) ("

Riverside

" or the "

Company

"), is pleased to announce the

completion of the first phase of drilling at the Union Project in Sonora, Mexico.

12 diamond core holes

were completed for a total of just over 1,600 metres across six priority targets. The work is being

advanced with funding through partner Questcorp Mining Inc. ("

Questcorp

") under the option agreement

announced earlier in 2025 with Riverside as Operator and managing the exploration program.

Program Highlights

12 core holes completed totaling >1,600 m.

Six targets drilled: Union Mine, Union Norte, Cobre, Luis, Famosa, and Famosa Mag.

Three past-producing mine areas tested adjacent to historic workings to evaluate continuity.

>700 half-core samples shipped; assays pending.

Holes oriented as angle and near-vertical to cut stratigraphy and structures typical of Carbonate

Replacement Deposit-type ("CRD") systems, with focus beneath oxidized horizons generally <150

m depth.

"This first exploration phase accomplished initial drill holes into 6 target areas. We tested multiple

shallow gold and base metals targets, confirmed the key carbonate host units recognized by historic

mining at Union and Famosa, and gathered the structural and alteration data to further progress efficient

mineral exploration," said Dr. John-Mark Staude, President and CEO of Riverside Resources. "This

historically mined CRD district, validated by new drilling and improved datasets, advances our geologic

model and supports the potential for a large-scale discovery. With six targets advanced and more than

700 samples at the lab, once results are received, we will scope the next exploration program and focus

on the most prospective trends indicated by assay results, stratigraphy, structure, and geophysics."

Drilling Update by Area

Union Mine

: Three holes at the Union Mine targeted manto horizons and chimney/feeder structures

adjacent to historic underground workings. This reconnaissance drilling was designed to evaluate

stratigraphy, alteration, and mineralization continuity typical of CRD systems.

Famosa Mine Area

: Four core holes tested a west-dipping dolomite manto target and adjacent

structures. Logging noted intrusive dikes and breccias; no geochronology has been completed.

Historical small-scale mining left surface dumps reported with gold grades of >0.5 oz/t Au (>15 g/t) in an

independent NI 43-101 report filed on SEDAR+, May 7, 2025, by Questcorp. An inclined shaft dipping

~70° to the west parallels the favorable horizon. Holes were drilled at angles toward the east to intersect

the target as close to perpendicular as practical and to evaluate continuity of alteration and

mineralization.

Union Norte

: Two initial holes tested the manto horizon within dolomitic carbonate strata to evaluate

continuity and geometry along favorable trends mapped near historic workings. This phase targeted the

westward extension. Follow-up work, including possible step-outs to the east, will be considered after

assays and geological interpretation.

Cobre and Luis

: Each target was tested to assess style, structure, and controls on mineralization.

Results to date show sulfides, mineralization types, and intrusions aligned with a carbonate-hosted

metals system.

Figure 1:

Map of drill targets and core drill hole locations for the 12 holes of Phase 1 program.

To view an enhanced version of this graphic, please visit:

https://images.newsfilecorp.com/files/6101/274043_4f76f41f0415684e_002full.jpg

Sampling and Assays

Core was logged, saw-cut, and half-core samples were shipped for analysis. Samples from the first

eight holes were delivered to Bureau Veritas (Hermosillo, Sonora) for gold fire assay, with pulps

forwarded to Vancouver, Canada for Inductively Coupled Plasma-Mass Spectrometry ("ICP-MS")

following four-acid digestion to determine silver, base metals, and pathfinders. Samples from the final

four holes were shipped to ACT Labs Zacatecas, where preparation, gold assay, and multi-element ICP

are completed in Mexico. Remaining half-cores are retained for reference. The final 4 holes of the

program were shipped to ACT Labs where they were similarly assayed using the same processing

methods but with their initial preparation and assaying completed in Zacatecas, Mexico using the same

ICP and gold fire assay methods.

Next Steps

After assays are received, the Company plans to announce results and begin work to integrate the full

exploration results including the assays, core logging, geophysics, advance detailed multi-element

geochemistry, and updated structural mapping to refine the CRD model and scope for a Phase 2

exploration campaign.

The Phase 2 campaign will likely include more extensive drilling and other

exploration work as this Phase 1 was only an initial sampling into some of the targets at Union.

This next

expanded drill program could take place in H1, 2026 as all permits and access are in good standing and

with the new data targets will be ready to explore.

Qualified Person & QA/QC:

The scientific and technical data contained in this news release pertaining to the Project was reviewed

and approved by Freeman Smith, P.Geo, a non-independent qualified person to Riverside Resources

Inc., who is responsible for ensuring that the information provided in this news release is accurate and

who acts as a "qualified person" under National Instrument 43-101 Standards of Disclosure for Mineral

Projects.

About Riverside Resources Inc.:

Riverside is a well-funded exploration company driven by value generation and discovery. The Company

has a solid balance sheet with no debt and less than 75M shares outstanding with a strong portfolio of

gold-silver and copper assets and royalties in North America. Riverside has extensive experience and

knowledge operating in Mexico and Canada and leverages its large database to generate a portfolio of

prospective mineral properties. Riverside has properties available for option, with information available

on the Company's website at

www.rivres.com

.

ON BEHALF OF RIVERSIDE RESOURCES INC.

"John-Mark Staude"

Dr. John-Mark Staude, President & CEO

For additional information contact:

John-Mark Staude

President, CEO

Riverside Resources Inc.

[email protected]

Phone:

(778) 327-6671

Fax:

(778) 327-6675

Web:

www.rivres.com

Eric Negraeff

Corporate Communications

Riverside Resources Inc.

[email protected]

Phone: (778) 327-6671

TF: (877) RIV-RES1

Web:

www.rivres.com

Certain statements in this press release may be considered forward-looking information. These statements can be identified by the use of

forward-looking terminology (e.g., "expect"," estimates", "intends", "anticipates", "believes", "plans"). Such information involves known and

unknown risks -- including the risk that the Transaction will not be completed as contemplates, or at all, availability of funds, the results of

financing and exploration activities, the interpretation of exploration results and other geological data, or unanticipated costs and expenses and

other risks identified by Riverside in its public securities filings that may cause actual events to differ materially from current expectations.

Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange)

accepts responsibility for the adequacy or accuracy of this release.

To view the source version of this press release, please visit

https://www.newsfilecorp.com/release/274043