Riverside Samples 7.30 g/t Gold from Rock Samples Along a 0.8 km Transect Expanding Target Zone at the Cecilia Project in Sonora, Mexico

Vancouver, British Columbia--(Newsfile Corp. - December 20, 2023) - Riverside Resources Inc. (TSXV: RRI) (OTCQB: RVSDF) (FSE: 5YY) ("Riverside" or the "Company"), is pleased to report on rock sampling and fieldwork from the Cecilia Gold-Silver Project (the "Project") in Sonora, Mexico. The results fit within the larger context of a district scale gold-silver composite dome system with superimposed gold-rich veins. Past drilling by Riverside intercepted high-grade gold in 4 of the 7 holes and this sampling over new areas, doubles the strike of the defined mineralization footprint This large footprint is consistent with other rhyolite dome gold systems including those in New Mexico like Mogollon and in Sonora like at La India mine of Agnico Eagle.

Key Highlights:

• 34 rock samples were collected at the primary targets.
• 22 samples in the main target "Cerro Magallanes" confirming Au grades up 7.3 g/t Au and Ag > 100 g/t.
• Five (5) primary structural trends were identified with field data and historic geochemical data reprocessing.
• Updated drilling permits, valid for the next several years, have been obtained along with signed agreements for surface access over the targets.

Riverside collected rock chip samples from selective areas along 0.8 km length in the Magallanes Target area that returned gold values in assays up to 7.3 g/t Au and 144 g/t Ag (Figure 1A., Table 1). The sampling confirms the consistent Au grades obtained in past surface workings and diamond core drilling that includes 24.2m @1.51 g/t Au in CED21-005 by the Company. The mapping and exploration activities combined with data reprocessing allows the company geologists to define the main structural trends (Agua Prieta, San Jose, North Breccia, Central and East trends) that are the main mineral corridors (Figure 2). The structural trends are interpreted as the surface expression of a rooted rhyolite dome system where higher grades lie at the base of the hill (Figure 1B). The geochemical data obtained, and the geologic mapping are helpful to refine the geological model for the deposit type and target delineation for the next drill program planned for 2024.

Figure 1. A. Plan view map of the Magallanes Target with some of the new geochemical sampling done recently and the defined structural trends. B. Schematic cross-section interpreting the convergence of the structural trends into the root of a mineralized rhyolite composite dome system (like those found at Yanacocha, Peru and San Julian, Mexico).

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Table 1: Selected assay results from Riverside's recent sampling at Cecilia.

Figure 2. North-looking oblique aerial photograph of the Magallanes Dome Complex with different targets. The dashed red lines indicate the trends that control -mineralization and that are interpreted to be rooted in the central portion of the dome creating the next focused drill targeting.

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Cecilia Project

The Cecilia project consists of six mineral concessions, collectively covering over 77 sq km (7,739 hectares) in size, thus a large district covered by the Company. The Project is located 40 kilometers southwest of the Agua Prieta border between Mexico and the USA, and 50 kilometers east of Mexico's largest mining complex, Cananea copper mining complex producing the largest amount of copper in Mexico.

In the Cecilia Project, the rhyolitic tuffs and dome complex units intrude and unconformably overlie a sequence of marine clastic sedimentary rocks consisting of interbedded siltstone and sandstone of the Cretaceous Cabullona Group which hosts gold mineralization in other portions of northern Sonora as well as here at Cecilia. The age of the mineralization obtained by Riverside yielded ca. 18 Ma using U-Pb in zircons in syn-volcanic mineralized rhyolite flow dome in the top of the sequence. This age for mineralization tied to magmatism has also been reported in large Au camps in Arizona (e.g. Oatman area, DeWitt et al.,1986).

Riverside work in the district has developed additional targets including the Cruz 1, Cruz 2, Cruz 3, Casa de Piedra, Los Llanos, and Magallancito targets (Figure 3). These targets represent different levels of exposure and make the Cecilia project a potential district for multiple gold discoveries.

Figure 3. Map of the district by Riverside with areas of clustering with gold mineralization and targets shown. Stratigraphic column with targets in stars for location in the stratigraphy similar to other major rhyolite dome districts where multiple targets in diverse structural settings.

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Qualified Person & QA/QC:

The scientific and technical data contained in this news release pertaining to the Cecilia Project was reviewed and approved by Julian Manco, P.Geo, a non-independent qualified person to Riverside Resources focusing on the work in Sonora, Mexico, 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.

Rock samples from the exploration program discussed above at Cecilia were taken to the Bureau Veritas Laboratories in Hermosillo, Mexico for fire assaying for gold. The rejects remained with Bureau Veritas in Mexico while the pulps were transported to Bureau Veritas laboratory in Vancouver, BC, Canada for 45 element ICP/ES-MS analysis. A QA/QC program was implemented as part of the sampling procedures for the exploration program. Standard samples were randomly inserted into the sample stream prior to being sent to the laboratory.

About Riverside Resources Inc.:

Riverside is a well-funded exploration company driven by value generation and discovery. The Company has over $6M in cash, 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. In addition to Riverside's exploration spending, the Company also strives to diversify risk by securing joint-venture and spin-out partnerships to advance multiple assets simultaneously and create more chances for discovery. 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

Mehran Bagherzadeh
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 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.

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