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Grid Metals Announces Maiden Mineral Resource at Donner Lake Lithium Property; Lease Agreement Signed for True North Mill Provides Additional Flexibility for Future Lithium Production

Resource Estimates

Grid Metals Announces Maiden Mineral Resource at

Donner Lake Lithium Property; Lease Agreement

Signed for True North Mill Provides Additional

Flexibility for Future Lithium Production

July 18, 2023 TORONTO -- Grid Metals Corp. (TSXV: GRDM; OTCQB: MSMGF) ("Grid"

or the "Company") is pleased to announce a maiden National Instrument 43 -101

compliant Mineral Resource Estimate ("MRE") on its 75% owned Donner Lake Lithium

Project in Manitoba, Canada of 6.81 million tonnes ("MMt”) (Inferred) grading 1.39%

Li2O. In addition, the Company has signed a binding lease agreement (the

“Agreement”) with 1911 Gold Corporation ("1911 Gold") to use its nearby True North

mill for the production of lithium spodumene concentrate. Today’s announcement

further Grid’s objectives of enabling near term production and growing its lithium

business in southeastern Manitoba with:

• Maiden resource of 6.81 MMt (Inferred) at 1.39% Li2O

• Lease of the True North mill - an existing processing facility will be reconfigured

to enable lithium spodumene production

• True North mill is a permitted gold mill utilizing a flotation circuit with nominal

annual capacity of 475,000 tonnes. Mill is leased for up to five years plus a two-

year cancellation period.

• True North tailings facility is also permitted (with an additional permit required

to reconfigure mill and tailings to process lithium).

• Contract signed with leading lithium processing engineering firm Primero Group

to complete scoping level mill reconfiguration study in the next 90 days.

• Grid also has ongoing discussions with Tantalum Mining Company of Canada

Limited for toll milling available resources at the currently operating Tanco

Mine – 35 km south of Donner Lake – a second potentially complimentary

lithium processing option

• Donner L ake resource remains open for expansion , and ongoing property

exploration is focused on generating new exploration targets.

Robin Dunbar, CEO of Grid Metals, commented , "We believe t he resource and mill

lease announced today are essential building blocks for the development of a lithium

production business focused in southeastern Manitoba. Our exploration team has

done a great job delineating a significant high -grade initial resource in eighteen

months at Donner Lake. We now have a resource at Donner Lake and two potential

low capital cost processing options within trucking distance. Going forward, we will

look to utilize the excellent infrastructure in the area and the well-defined permitting

process in Manitoba. Our First Nation relationships are also key as we move forward

with this exciting project. We feel that Grid Metals offers a unique opportunity in the

junior lithium developer space to expedite production by leveraging nearby existing

milling infrastructure.”

Discussion of Key Points:

• Global maiden resource estimate of 6.81 MMt grading 1.39% Li2O consists of

2.10 MMt grading 1.42% Li2O of Open Pit resources (cut-off grade of 0.3% Li2O)

and 4.71 MMt grading 1.37% Li2O of below pit underground resources (cut-off

grade of 0.5% Li2O) from the Main Dyke and Northwest (“NW”) Dyke.

• The mineral resources are hosted by steeply dipping pegmatite dykes that are

exposed at surface and display consistent widths, spodumene content and

lithium grade.

• Lithium mineralization at the Main and NW dykes remains open to depth with

strong Li2O values in many of the deepest holes.

• The Company has identified a number of other exploration drill targets at

Donner Lake and has an extensive land position it is actively exploring.

• The True North mill is part of an integrated, fully permitted gold mine, mill and

tailings complex last operational in November 2022. It is located 85 km by road

from the Donner Lake Property. An application to permit the processing of

lithium material at the True North mill will be required.

• Primero Group Ltd. (“Primero”), one of the pre-eminent engineering consulting

firms in the lithium industry, has been engaged to complete a plant

reconfiguration scoping-level study to assess the viability and cost of

reconfiguring the True North mill to process spodumene-bearing material. This

study is expected to be substantially complete before the end of the 90-day due

diligence period (stipulated in the Agreement with 1911 Gold) and the signing

of a more detailed definitive lease agreement.

• In addition, Grid is in continuing discussions with the Tantalum Mining

Corporation of Canada Limited to reach a definitive agreement regarding terms

of toll milling of Donner Lake feed at the Ta nco minesite. Grid Metals has a

pre-production MOU with Tanco to process lithium material at its operational

lithium circuit ( see October 17, 2022 press release entitled “Grid Metals Corp.

Signs Pre-Production MOU With Tanco Lithium Mine”).

Maiden Resource at Donner Lake

The maiden lithium resource estimate was prepared by SGS Geological Services

("SGS") and is reported in accordance with National Instrument 43 -101 ("NI 43-101")

standards. The NI 43-101 technical report for the resource estimate will be accessible

on SEDAR (www.sedar.com) within 45 days of this news release.

The current mineral resource estimate comprises spodumene-enriched pegmatite

from three northwest striking pegmatite dykes including the Main Dyke , a smaller,

sub-parallel dyke located ~50 metres north of the Main Dyke (the " Hangingwall

Dyke"), and the NW Dyke. The Main Dyke interpretation, including the Hangi ngwall

Dyke, used 57 drillholes totalling 13,478 metres of core. The NW Dyke interpretation

used 34 drillholes totalling 7,815 metres of core. The resources cover an approximate

strike length of 1,100 metres for the Main Dyke and 700 metres for the NW Dyke, with

vertical extents of ~300 metres and ~250 metres, respectively. Open pit resources

cover the uppermost ~100 metres in both the Main and NW dykes and are constrained

by optimized pit models. Initial metallurgical testwork (see June 26, 2023 press release

entitled “Grid Metals Corp Reports Positive Metallurgical Test Results from Donner

Lake Lithium Property) confirms that spodumene accounts for over 90% of the lithium-

bearing minerals in the Main and NW dykes.

The open -pit resources total 2.10 MMt grading 1.42% Li 2O, including 1.14 MMt

grading 1.48% Li2O at the Main and Hangingwall dykes, and 0.96 MMt grading 1.36%

Li2O at the NW Dyke. The underground resources total 4.71 MMt grading 1.37% Li2O,

including 3.67 MMt grading 1.39% Li2O at the Main Dyke and 1.04 MMt grading 1.11%

Li2O at the NW Dyke. Hole locations are shown in Figure 1. Please refer to Table 1 for

additional information. The mineral resources remain open at depth, particularly at

the Main Dyke (see longitudinal section, Figure 2, below). In addition, the Company is

actively exploring for additional spodumene -bearing pegmatites at Donner Lake and

anticipates a new phase of exploration drilling later in the year.

The mineral resource estimate was created and estimated using SGS’s proprietary

modelling software, Genesis, and the open pit shells were created in Whittle software.

The mineralised wireframe was restricted to drill core that had been logged as lithium-

bearing pegmatite. The block models were created using a 5m x 3m x 5m block size in

the x -, y - and z -planes, respectively. Grade was estimated using inverse distance

squared (ID2) methodology and three passes of estimation. All resources are classified

as Inferred Resources, consistent with the 2014 CIM Definitions for Mineral Resources

and Mineral Reserves.

Table 1: Inferred Mineral Resource Estimate for Donner Lake Lithium Project.

Notes for the Mineral Resource Estimate:

1. The Mineral Resource Estimate (MRE) has an effective date of the June 27 , 2023. The Qualified Persons for the MRE

are Mr. Rohan Millar, P.Geo. an employee of SGS.

2. The classification of the current Mineral Resource Estimate into Inferred Resource is consistent with current 2014 CIM

Definition Standards - For Mineral Resources and Mineral Reserves.

3. All figures are rounded to reflect the relative accuracy of the estimate and numbers may not add due to rounding.

4. All Resources are presented undiluted and in situ, constrained by continuous 3D wireframe models, and are considered

to have reasonable prospects for eventual economic extraction.

5. Mineral resources which are not mineral reserves do not have demonstrated economic viability. An Inferred Mineral

Resource has a lower level of confidence than that applying to an Indicated Mineral Resource and must not be

converted to a Mineral Reserve. It is reasonably expected that the majority of Inferred Mineral Resources could be

upgraded to Indicated Mineral Resources with continued exploration.

6. It is envisioned that parts of the Donner Lake deposit may be mined using open pit mining methods. In-pit mineral

resources are reported at a cut-off grade of 0.3% Li2O within a conceptual pit shell.

7. The results from the pit optimization are used solely for the purpose of testing the “reasonable prospects for economic

extraction” by an open pit and do not represent an attempt to estimate mineral reserves. There are no mineral

reserves on the Property. The results are used as a guide to assist in the preparation of a Mineral Resource statement

and to select an appropriate resource reporting cut-off grade.

8. Underground (below-pit) Mineral Resources are estimated from the bottom of the pit and are reported at a base case

cut-off grade of 0.5% Li2O. The underground Mineral Resource grade blocks were quantified above the base case cut-

off grade, below the constraining pit shell and within the constraining mineralized wireframes. At this base case cut-

off grade the deposit shows good deposit continuity with no orphaned blocks.

9. Bulk density values (specific gravity 2.7 grams per cubic centimetre) were determined based on physical test work

from each deposit.

Classification (Cut-Off

Grade) Deposit Inferred Resource

(tonnes)

Grade

(% Li2O)

Main Dyke 1,145,000 1.48%

NW Dyke 955,000 1.36%

Total 2,100,000 1.42%

Main Dyke 3,669,000 1.45%

NW Dyke 1,042,000 1.11%

Total 4,710,000 1.37%

Main Dyke 4,814,000 1.46%

NW Dyke 1,997,000 1.23%

Total 6,810,000 1.39%

GLOBAL

Open Pit

(0.3% Li2O)

Underground

(0.5% Li2O)

10. The in-pit base case cut-off grade of 0.3% Li2O considers a lithium concentrate 6% (LC6) Li2O price of US$1800/tonne, a

mining cost of US$3.50/t rock and processing, treatment and refining, transportation and G&A cost of US$45.00/t

mineralised material, and an overall pit slope of 55 degrees.

11. The below-pit base case cut-off grade of 0.5% Li2O considers a lithium concentrate 6% (LC6) Li2O price of

US$1800/tonne, a mining cost of US$60.00/t rock and processing, treatment and refining, transportation, and G&A

cost of US$45.00/t mineralised material.

12. The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation,

socio-political, marketing, or other relevant issues.

Figure 1: Plan view map showing surface traces of resource delineation drill holes and

the three spodumene -rich pegmatite dykes at Donner Lake that host the current

lithium resource estimate.

Figure 2: Longitudinal section, looking northwest, showing pierce points of 2018, 2022

and 2023 Main Dyke drill holes. Interval assays are estimated to represent 50 to 90

percent of the true thickness depending on the dip of the holes.

True North Mill Overview

The True North mill, located in Bissett, Manitoba, sits approximately 85 km by existing

all-weather road from the Donner Lake Lithium Project (see Figure 3 ). The original

processing facility at the site was constructed in 1931, but was destroyed by a fire in

1980. The facility was subsequently reconstructed in 1996 with an operating capacity

of 900 tonnes per day (“tpd”), and the mill capacity was increased to 2,300 tpd in 2011.

Since then, the mill capacity has been scaled back to 1,300 tpd. The mill was l ast in

operation in November 2022 and was reprocessing gold tailings.

The current processing facility consists of crushing, milling, centrifugal gravity

concentration, and flotation circuits . Initial metallurgical test results from Donner

Lake ( see June 2 6, 2023 press release entitled “Grid Metals Corp Reports Positive

Metallurgical Test Results from Donner Lake Lithium Property” ) concluded that

standard flotation was the best method for recovering lithium from the Donner Lake

samples. Heavy Liquid Separation, as an initial evaluation of the Dense Media

Separation process, was conducted, and it was determined that this process may not

be of material value for enhancing lithium recovery.

Primero Engineering Engagement - Grid Metals has engaged Primero to complete a

plant reconfiguration study including preliminary capital costing analysis. Primero is

one of the pre-eminent engineering consulting firms with extensive experience in the

lithium sector. Primero has worked with a number of lithium companie s includ ing

Sigma Lithium, Core Lithium and Sayona Mining, amongst others.

Figure 3: Location of the True North m ill in the Rice Lake greenstone belt showing

proximity to the Donner Lake lithium property and the City of Winnipeg.

Figure 4: Aerial View Of True North Mill

Figure 5 Primary Mill - True North Mill