Sierra begins airborne magnetic survey at its gold projects in Nevada

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For Immediate Release

Sierra Grande Begins Airborne Magnetic Survey at its B&C

Springs and Glitra-Sat Gold Projects in Western Nevada

Surrey, British Columbia, June 28, 2022, Sierra Grande Minerals (the “Company” or “Sierra”)

(CSE: SGRO) (OTCQB: SIERF) (FSE: SRR) ("Sierra" or the "Company") is pleased to announce that

it has commenced drone-borne magnetic (drone-mag) surveys at both its B&C Springs (“B&CS”) and

Glitra-Sat gold projects in Western Nevada (see Images 1-3). Sierra will also be conducting geological

mapping, prospecting and rock and soil geochemical sampling work while on site. The airborne

surveys will be conducted by Pioneer Exploration.

The drone-mag surveys at B&CS and Glitra-Sat will cover the entirety of the two properties. Flight

lines will be spaced 50m apart and flown on azimuths perpendicular to known and /or interpreted

stratigraphic, structural, and mineralized and altered trends (see Images 1-2). Technical details of the

surveys, and products thereof, are given below.

The aim of the surveys is to outline altered and mineralized trends on the properties, which may

be expressed, for example, as magnetic lows reflecting magnetite destructi ve alteration within

relatively magnetic host rocks . This should prove particularly helpful in areas where mineralized

trends appear to continue beneath overburden-covered areas.

At the Glitra-Sat property a number of areas fall into this category, such as along trend both north and

south of the Glitra occurrence, and at the Sat occurrence, where a known gold mineralized zone is

covered to the east by unconsolidated material of the pediment, and to the south by alluvial deposits

in the Stonehouse valley (see Image 2).

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On the B&CS property a similar situation exists. There , extensive but generally thin overburden at

the head of a broad and gently -sloping pediment obscures a large area between precious metals

showings on the B&CS propert y. On the west and abutting Almadex’s Davis Gold property are

recently-sampled showings which yielded a number of high -grade grab samples, including those

returning 17.35, 30.9 and 150.5 g/t Au (see Image 1). On the east is the Mildred Mine area, where soil

sampling yielded a number of highly anomalous samples (please see News release dated August 31,

2021, and Image 1). The new samples were collected by prospectors earlier this year, following the

Company’s recognition of the potential of this area, and after staking program. Furthermore, limited

outcrop exposed in drainages lying within the bounds of the wide pediment area between the two

gold-mineralized areas on the Company’s claims indicates that the overb urden is thin and that

alteration is at least locally present along structures within the rocks exposed therein.

Following the drone-mag surveys, the Company expects that follow-up work will be undertaken

with an eventual goal to define drill target s along trends showing the greatest potential to hos t

economic mineralization. That work is expected to include ground-based CSAMT (controlled source

audio-magnetic telluric) and/or IP (Induced Polarization) geophysical surveys, as well as d etailed

mapping and sampling.

“As per our 2022 exploration plan, we are very pleased to continue exploration at our

gold projects in Nevada. It will be exciting to see the results of these surveys and to

plan aggressive follow-up work. With numerous high-tenor soil geochemical targets at

both Glitra-Sat and B&C Springs, our expectation is that the airborne magnetic data

yields further encouragement that carries us closer to our goal, which is ultimately to

drill-test some high -potential targets on both properties ” commented CEO, Sonny

Janda.

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About the Projects

B&C Springs

The B&C Springs property is located in the southern Paradise Range in west-central Nevada, within

the Fairplay Mining District. The property abuts Almadex Minerals Ltd.’s Paradise Valley project

on its east side (see Image 1).

Recent soil geochemical sampling at B&CS clearly shows that anomalous copper, molybdenum and

silver geochemistry is closely associated with a west -northwesterly trending porphyry dike swarm

crossing the northern part of the property. The anomalous zone is extensive, running from beyond the

previously drilled Mo -Cu-Ag mineralized zone at B&C Springs on the east, to beyond the western

boundary of the claim group, a distance of over 4 km. The anomalous values are of high tenor, with

a broad zone, nearly a km in width, that has many values exceeding 100 ppm copper, and which range

up to 1 ,200 ppm copper. Elevated Ag, Mo, Au, Hg and Sb are commonly associated with the

anomalous copper values, but this latter expression is most evident in a semi -circular “halo” around

the northern margins of the greenstone “cap” to the B&C Springs Mo-Cu-Ag mineralized zone.

In the vicinity of the Mildred Mine and toward the southwestern part of the property, where there are

numerous historical prospecting pits, adits and shallow shafts, the soil geochemical response for gold

and silver confirms the potential of that area for precious metals mineralization. This expression hints

at further potential for precious metals to the west beneath the shallow overburden of the pediment

area, and that potential was still further reinforced by the results of Sierra’s recent staking -related

prospecting program, in which grab samples returned values ranging up to 150.5 g/t gold (see above

and Image 1).

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Image 1. B&C Springs Plan View with Highlighted Soil Geochem Data and Survey Area

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Glitra-Sat

The Glitra/Sat properties are sister properties, with the relatively small “Orbit” property lying between

(see Image 2). They are located in Pershing County, western Nevada, in the Seven Troughs Range of

the Farrell Mining District, which hosts numerous historical and modern‐day mineral occurrences and

deposits. The properties are contiguous with Millennial Precious Metals Wildcat Project, which hosts

a 43-101 compliant inferred mineral resource of 67.6 million tons grading 0.37 g/t Au totaling 824,000

oz Au, and they lie a few kms north of Timberline Resources Seven Troughs Project (see Image 2).

On the Glitra property, r esults from a previously completed soil -geochemistry su rvey identified a

promising +1km north-northeast trending mineralized and altered zone with a pronounced epithermal

Au-Ag-As-Hg signature and a width ranging up to 150 to 200 metres.

At Sat, strong soil sampling results also appear to outline a north-northeast trending anomalous zone,

or zones, with a pronounced Au -Hg-As-Ag signature that most likely reflects structurally -hosted

epithermal mineralizing system(s) (see Image 2).

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Image 2. Glitra-Sat Plan View with Highlighted Soil Geochem Data and Survey Area

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Image 3. Nevada Regional Setting with Sierra Projects

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Drone-Mag Survey Technical Details

The drone-mag survey at B&CS will feature 50 metre line spacings along NE -SW azimuths, with a

total planned survey of 1,210 line kilometres (see Image 1.).

The drone-mag survey at Glitra-Sat will also feature 50 metre line spacings but along E-W azimuths,

with a total planned survey size of 648 line kilometres (see Image 2.).

Data Deliverables for the surveys will include:

➢ Technical Reports

➢ Total Field Magnetics Maps

➢ First Vertical Derivative Map

➢ Analytical Signal Map

➢ Processed, micro-leveled line by line database of the magnetic data

➢ Raw survey data and geodatabase digital files and base station data

➢ 12m and 5m resolution DSM files

Technical data pertaining to this new release was reviewed and approved by Charles J. “Charlie”

Greig, MSc., P.Geo., a qualified person under National Instrument 43-101.