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Riverside Completes Acquisition of the Los Cuarentas Project From Millrock Mexico

Mergers & Acquisitions Property Options & Staking

Riverside Completes Acquisition of the Los Cuarentas Project From Millrock

Mexico

VANCOUVER, British Columbia, Sept. 11, 2019 -- Riverside Resources Inc. (“Riverside” or the “Company”) (TSX-V:

RRI) (OTCQB: RVSDF) (FSE: R99), is pleased to announce that the Los Cuarentas district acquisition has been completed.

Riverside announced the deal to acquire this Project as part of a portfolio of assets from Millrock Resources Inc. (“Millrock”) in

June of 2019 (see press release June 26, 2019) for four (4) mineral properties in Sonora, Mexico. The Los Cuarentas Project

(the “Project”) is located in northeastern Sonora, Mexico, within the Los Cuarentas district, which is part of the larger Arizpe

Metallogenic Cluster.

The Project is located 17 km northwest of SilverCrest Metals’ Las Chispas Mine. SilverCrest recently released a PEA

(Preliminary Economic Assessment), showing an average annual production of 9,559,000 oz AgEq 1 over the life of the mine.

The Los Cuarentas Project is also located 15 km northeast of Premier Gold’s Mercedes Mine, which produced 89,699 oz Au

and 321,814 oz Ag in 20182 (see Figure 1 below).

The Los Cuarentas Project produced in excess of 100,000 ounces of gold from historical mine operations within epithermal

vein structures in the 1950s. Last year, Millrock completed a surface sampling program that returned numerous multi-gram

assays including one up to 17.5 g/t Au over 1 m. An induced polarization survey (IP) was also completed by Centerra Gold in

2016 while under option from Millrock that identified a strong resistive body that appears to coincide with the surface

expression of the Santa Rosalia Sur vein systems. Riverside has identified three (3) targets from mapping and sampling

through integrating past and current data to refine a go forward work program. The Santa Rosalia target is the highest priority

of the 3 targets and is defined by past open cut and underground vein mining where recent sampling has shown a strike length

of more than 500 m and open to the east and west.

Disclaimer: Assay results from previous operators work on the Los Cuarentas Project is historical. The reliability of historical

data is uncertain but is considered to be relevant by Company management; however, there is a risk that the Company’s

confirmation work or future drill testing may produce results that substantially differ from the historical results.

Riverside’s President and CEO, John-Mark Staude, stated: “We are delighted to have closed the transaction and to be

working with our dedicated Mexican team to progress these former mine areas with modern exploration and drilling. The recent

success by companies like SilverCrest Metals, Premier Gold Mines, First Majestic, Agnico Eagle and others surrounding our

project demonstrates the excellent potential for new discoveries in the district.”

Figure 1: Location map of the Los Cuarentas Project including neighboring mines in NE Sonora, Mexico

Riverside’s exploration team is currently in the field completing mapping and sampling work along strike of the known vein

systems and believes there is also great potential to identify new veins across the greater property package.

Targets:

Riverside has identified three (3) primary targets at the Los Cuarentas Project; the Santa Rosalia target, the Santa Rosalia Sur

target, and the El Sombrero target. Riverside geologists will focus their initial efforts towards the Santa Rosalia target utilizing

past data to refine the target area and work program. The Company is also working on interpretations of the structural control

of the high-grade ore shoots to better understand and delineate the volcanic-hosted, low sulfidation veins found on the property.

Santa Rosalia:

The historical mine area can be accessed via old shafts and adits. The high-grade samples taken by Millrock Resources in

2018 of 5 g/t Au and up to 17 g/t Au within structures makes this an intriguing exploration target. The Santa Rosalia target

shows clay alteration with inward zoning of silicification grading into a well-defined silicified vein structure and is a priority for

drill discovery. Previous mapping, sampling, underground work and other research studies of the historical mine operations

include: Santa Rosalia Mining, Centerra Gold, Paget Minerals, and the Mexican Geological Survey providing a wealth of data

for targeting and drilling.

Santa Rosalia Sur:

Santa Rosalia Sur target is located southeast from the historical Santa Rosalia mine area and has been a focus for recent

exploration by Centerra. Centerra conducted an IP survey, detailed soil geochemical survey, detailed rock sampling and

geologic mapping. The IP was conducted by Zonge Geophysics in December 2016. The Santa Rosalia Sur target comprises a

well-defined 800 m long, structural zone that has been mapped and sampled for alteration minerals (Terraspec) for vectoring

and targeting.

El Sombrero:

At the El Sombrero target, the alteration is very extensive showing silica caps indicative of high-level boiling zones within an

epithermal system. The El Sombrero target is located E-SE of Santa Rosalia Sur and comprises altered andesites, dacites

and agglomerates. This alteration in conjunction with Centerra Gold’s geochemical soil survey and selected rock chip samples

has delineated this region as a third priority target.

Geology:

The historical Santa Rosalia area comprises a series of mineralized (< 1 m to 2.5 m wide) parallel, low sulfidation epithermal

veins of banded crystalline to cryptocrystalline quartz and calcite. Mineralization shows gold, silver, galena, argentite,

acanthite, sulfosalts, minor chalcopyrite and pyrite. Textures observed are typical of a low sulfidation epithermal system and

include the presence of incipient banded quartz, quartz breccia, silica after bladed calcite and quartz veinlet arrays inside fault

breccia and gouge. Vein flexures and cross intersections provide some of the higher-grade bonanza shoots, which remain to

be further explored over the strike length.

The historical mine workings, which have been abandoned since the 1950s, consist of a vertical stope open to surface with

horizontal extensions reaching out possibly 250 meters. There are several tens of thousands of tons of material based upon

Millrock and Paget’s calculations near the abandoned mill structure. While the extent of the workings is not fully known, there

are indications that they may extend vertically down to possibly 230 meters. Riverside will be targeting along strike of the

named veins and will include sampling a number of recently discovered veins.

Veins are hosted in andesitic, volcanic rocks that show strong alteration minerals including sericite and high acid conditions

clay minerals. The stratigraphy is similar to that of Mercedes and Las Chispas mines where sedimentary units are overlain by

andesitic flows and flow breccias.

Option Payments & Royalties (all in USD):

Riverside will be assuming Millrock’s remaining options payments for the Los Cuarentas Project. Millrock has previously paid

$28,500. Riverside’s payment schedule includes: September 2019 of $25,500 (paid), $18,000 due February 2, 2020,

$42,000 due August 2, 2020 and $42,000 due February 2, 2021 to complete all payments in USD of $156,000 for the

Project. For Santa Rosalia there is a 0.5% NSR to Millrock and on the surrounding concession there is an NSR to Sandstorm

Gold Royalties of 1.5% on Au and 1% on other metals.

Qualified Person & QA/QC:

The scientific and technical data contained in this news release pertaining to the Los 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 has not verified any of the historical assay

results at the Project. The Company’s plan is to begin an exploration program to confirm historical results in the near future.

About Riverside Resources Inc.:

Riverside is a well-funded exploration company driven by value generation and discovery. The Company has no debt and fewer

than 63M shares outstanding with a strong portfolio of gold-silver and copper assets in North America. Riverside has extensive

experience and knowledge operating in Mexico 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 additional properties available for option, with more 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

Raffi Elmajian

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.

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.

1 http://www.silvercrestmetals.com/_resources/704-ENG.VMIN03016-05-Las-Chispas-PEA_a190719_SEDAR.pdf

2 https://www.premiergoldmines.com/2018-4th-quarter--year-end