Riverside Resources Drills New Gold Vein System Developing an Updated Exploration Model at the Cuarentas Project in Sonora, Mexico

Vancouver, British Columbia--(Newsfile Corp. - July 29, 2021) - Riverside Resources Inc. (TSXV: RRI) (OTCQB: RVSDF) (FSE: 5YY) ("Riverside" or the "Company"), is pleased to present the new exploration model for the Cuarentas Project in Sonora, Mexico. This new model results from the compilation of the updated geochemistry processing from an external expert geochemist consultant, combined with the new proof of concept drill results from hole LC20-010. This is the first drill hole testing the Santa Rosalia Sur target by Riverside.

Highlights from the hole LC20-010 discovering a new drilled vein system:

• 3.15 m at 0.36 g/t Au including 0.7 m at 0.88 g/t Au
• 1.55 m at 0.58 g/t Au including 0.65 m at 1.05 g/t Au

Riverside's President and CEO, John-Mark Staude: "We are excited to receive the new and first ever drill assay results from the Santa Rosalia Sur target area which begins to outline a strong drill target area at the Cuarentas Project. We are optimistic that with just one initial hole the campaign has encountered two vein areas wide open at strike and depth to continue seemingly above a degassing Laramide porphyry Cu-Au center."

The Cuarentas epithermal vein drilled mineralized area intersected at surface and appears to be the upper part of a copper-gold porphyry system that is potentially responsible for the extensive >6 km² area including sericite and pyrophyllite alteration. Some of the key features include:

• A major NW oriented fault corridor, linked with a 2.5 km continuous strong (>0.3 g/t Au) gold anomaly along trend.
• Detailed and regional mapping by Riverside defines post-mineral cover boundary which was previously interpreted as the limit of the system and is now clearly seen as younger cover with the system being significantly larger and only a fraction exposed at the surface. Channel rock-sampling highlighting up to 3.4m @ 9.1 g/t Au at the surface of the single drill hole demonstrates potential for more gold in further drilling of this Santa Rosalia Sur target.
• Strong geophysical texture with airborne and ground magnetic features defines the continuity of main shear zones which control veins and then downward into a porphyry Cu-Au targeting at depth. Further drilling is warranted to test the magnetic features.
• Extensive pyritic halo across the entire property with zones of white micas and pyrophyllite indicate higher temperature vectors toward an undrilled porphyry system.
• Extensive database from work done by Paget, Millrock, Centerra, Hochschild and Riverside gives abundant data now compiled.
• Historical production reporting more than ten old adits and up to 100,000 tonnes mined from the 1950s.
• A total of 14 historical and recent drill holes, which are evidence for mineralization, alteration useful for vectoring and targeting for future work.

And recently:

• Defined Intermediate Sulfidation system at Santa Rosalia Sur which is vectoring toward a potential feeder zone; Geochemistry analysis are showing zoning of higher ratios which compiled with mapping and drilling is leading to a potential feeder zone (see Figure 1 below).
• Single drill hole at the Santa Rosalia Sur target by Riverside has intersected wide pyritic zones, similar to the upper parts of known porphyry systems and vein halos in this Arizpe Sonora District including like portions of Las Chispas Mine and also Mercedes Mine which are nearby neighbors to the east and west respectively. Drilling here at Santa Rosalia Sur cut a gold rich mineralized quartz vein zone beneath post-mineral cover (see Figure 3 below - core pictures). Geologically, this hole is important for interpretation and vectoring purposes.

Figure 1: Two maps of the Cuarentas Project highlighting above the geochemistry ratio distributing spatial (top map), and Interpretation for targeting next drill program (bottom map of same area as top map).

To view an enhanced version of Figure 1, please visit:
https://orders.newsfilecorp.com/files/6101/91539_7982025584517b94_002full.jpg

To conclude, after taking into consideration, Riverside is highlighting the possibility of a feeder system of intermediate sulfidation along the Testerazo fault corridor. The latter is known to be involved as a deep-seated structure within the Arizpe district, and regionally associated with porphyry feeder further to the south. Distribution of evidence is showing an opportunity for more geophysics within the southern block, near the Sombrerito target, which then will lead to test drilling (see Figure 2 below).

Figure 2: Interpretative SW-NE Cross Section of the Cuarentas Project, indicating prospective target at depth for drill testing of feeder zone (based on current drill and surface data).

To view an enhanced version of Figure 2, please visit:
https://orders.newsfilecorp.com/files/6101/91539_7982025584517b94_003full.jpg

Overall, the Cuarentas district is particularly prolific, with extensive alteration and can be seen at surface with extensive jarosite, limonite and pyrite non-oxidized in drill holes (see Figure 3 below). This pyritic halo extends for multiple km². Zones of higher temperature clays are an important vector for the feeder zone, which are defined in Figure 1 above.

Figure 3: Core pictures of the hole LC20-010. Left picture: sheeted vein zone - and gold interval upper part of the core hole; Right picture: Example of pyritic halo intersected in drill hole.

To view an enhanced version of Figure 3, please visit:
https://orders.newsfilecorp.com/files/6101/91539_7982025584517b94_004full.jpg

Qualified Person & QA/QC:

The scientific and technical data contained in this news release pertaining to the Cuarentas Project was reviewed and approved by Freeman Smith, P.Geo, a non-independent qualified person to Riverside Resources, who is responsible for ensuring that the geologic 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.

Riverside completed a QA/QC program as part of the drilling program with about 10% of the samples assayed being control samples. Standards and blanks were inserted approximately every 20 samples and duplicates every 30 samples. Drill samples 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.

Rock samples from the previous exploration programs discussed above at Cuarentas were taken to 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 $4M in cash, no debt and less than 72M 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 own 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.
info@rivres.com
Phone: (778) 327-6671
Fax: (778) 327-6675
Web: www.rivres.com

Raffi Elmajian
Corporate Communications
Riverside Resources Inc.
relmajian@rivres.com
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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