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Grid Metals Announces Indicated Open-Pit Mineral Resource of 46.2 Million Tonnes at MM Copper/Nickel Project in Southeastern Manitoba

Resource Estimates

Grid Metals Announces Indicated Open-Pit Mineral Resource of 46.2 Million

Tonnes at MM Copper/Nickel Project in Southeastern Manitoba

May 6, 2024 TORONTO -- Grid Metals Corp. (TSXV:GRDM ; OTCQB:MSMGF) ( "Grid" or the

"Company") is pleased to announce an updated Mineral Resource Estimate ( "MRE") for its

copper/nickel MM (previously “Makwa Mayville”) Project in southeastern Manitoba, prepared in

accordance with CIM (2019) Best Practice Guidelines . The resource estimate contains two

separate deposits located 35 km apart and approximately 145 kilometres from Winnipeg the

capital of Manitoba. Grid has consolidated the majority of the prospective copper-nickel mineral

tenure of the highly prospective Bird River Greenstone Belt including several other deposits near

the Makwa and Mayville resources. Concurrently with the new resource estimate the Company

has completed a Project wide geophysical review which has identified a number of new high

potential targets for drilling. An initial drill program is in planning and expected to commence

later in 2024. The Company is seeking financing and/or strategic partnerships to actively develop

the Project.

Mineral Resource and Project Highlights:

The Indicated mineral resource amenable to open pit mining and constrained within pit-shells is

tabulated below:

Deposit Mining Tonnage Ni Cu Co Pd Pt Au NiEq Cu Eq

MMT % % % g/t g/t g/t % %

Mayville Open Pit 32.02 0.16 0.40 0.01 0.13 0.05 0.05 - 0.61

Makwa Open Pit 14.22 0.48 0.11 0.02 0.37 0.10 - 0.75 -

*See details of the Mineral Resource Estimate including calculation methods used to determine the copper

equivalent (CuEq) and nickel equivalent (NiEq) grades presented in Tables 1A and 1B.

• Contained metal content in the indicated open pit category includes 317 million pounds

of copper, 263 million pounds of nickel and 452,000 ounces of combined palladium,

platinum and gold.

• Both deposits remain partly open along strike and at depth , and the Company holds the

mineral rights to three other near-surface mineral deposits in the belt that could

augment the mineral resource inventory in the future.

• Both deposits have had extensive metallurgical test work completed over multiple

campaigns with results indicating that saleable sulfide concentrates can be produced

(nickel at Makwa; separate copper and nickel concentrates at Mayville).

• The m ain factors contributing to the increased resources from previous estimates are

improvements in modelled metallurgical recoveries, changes in metal prices and forex

used in the resource calculation and additional drilling.

• The Mayville Deposit has no royalty; the Makwa Deposit has a 1% NSR royalty of which

one half of a percent can be re-purchased for CAD$500,000.

• There are no offtake obligations on either of the deposits . The Company is currently

seeking expressions of interest to fund resource expansion and project development

through marketing of nickel and copper offtake rights for the project.

• The target/model for the project is + 80 million tonnes of open pit resources augmented

by the delineation of high-grade massive sulfide deposits throughout the belt.

• The Company has the mineral rights to the majority of the prospective Bird River

Greenstone belt which has a geologic analogue to the McFaulds Lake Greenstone Belt

which hosts the Ring of Fire deposits (see reference 2 at end of the press release)

• Among the economic parameters used in the mineral resource estimate, metal prices

for the key metals are US$3.75 lb for copper and $9 lb for nickel.

• Strip ratios for the resource shells were 3.2 for Mayville and 4.7 for Makwa and are

provided in the resource Tables 1A and 1B.

• Company plans to commence an initial phase of exploration drilling later in 2024 to test

high priority nearby targets including possible massive sulphide targets identified from

the recent geophysical review.

Robin Dunbar, CEO of Grid Metals, commented , "The resource estimate announced today

provides impetus for further exploration and continued expansion of the MM copper/nickel

Project. The MM Project resource is a conventional and near surface copper-nickel sulfide

resource with readily apparent upside. The Project is ideally located to service critical metals

demand in North America. The Mayville deposit is located directly adjacent to the Company’s

advanced exploration stage Donner Lithium Project which is currently progressing through the

mine permitting process. We see tremendous synergies between our copper/nickel and lithium

project development plans as we continue to build the mineral resources necessary to develop

an important critical metals production and processing hub in a Tier 1 mining jurisdiction."

Project Overview

The MM Project includes a copper -rich (Mayville) and a nickel -rich (Makwa) disseminated

magmatic sulfide deposit along with three additional near-surface deposits (Page, Ore Fault, and

New Manitoba) which were acquired by Grid in April 2023 . The Mayville and Makwa deposits

are located in the northern and southern parts of the Bird River Greenstone Belt, respectively, in

southeastern Manitoba (see Figure 1). The Bird River Greenstone Belt and its mineral occurrences

have been the subject of multiple research projects including research work completed under

the Targeted Geoscience Initiative by the Canadian Geological Survey. The Project area has been

identified as being a direct analogue to the Ring of Fire belt in northwestern Ontario (Houlé et

al., 2020) which hosts several significant mineral deposits.

The Project consists of a mining lease and mineral claims held by the Company and its

subsidiaries. It is readily accessible year -round, by provincial highways from the capital city of

Winnipeg located ~145 km to the southwest. The Mayville deposit is situated two km north of

the Company’s Donner Lithium Project where the Company has published a NI 43-101 Resource

Estimate Technical Report. Both the Donner and MM Projects will benefit from efficiencies in

exploration, government and First Nations relations, permitting and infrastructure.

In total, 99 mineral claims and one mineral lease (Makwa) are held for base metal exploration by

the Company and its subsidiaries. A further 51 mining claims are under option from Gossan

Resources with a $300,000 option payment remaining under the option and due in April 2025 .

The Makwa Deposit is held under a Mineral Lease granted by the Province of Manitoba that

expires in 2040 and is subject to annual payments of approximately $10,000 per year. Under the

mineral tenure system in Manitoba, assessment credits are “banked” to enable the claims to be

held without annual payments provided sufficient exploration credits are expended on the

Property. Currently, the Company has sufficient exploration credits to keep the Project in good

standing for over 10 years.

Figure 1: Location of the MM Copper/Nickel Project and the Donner Lithium Project in

southeastern Manitoba

Exploration Potential

The Company views the updated MM resource estimate as an important base upon which it can

expand. The Company notes that by far the majority of the exploration completed to date has

focused on near surface disseminated mineralization. The higher-grade cores of the deposits and

higher-grade values associated with massive sulfides in multiple drill holes give clear indication

that the potential for higher-grade massive sulfide is evident throughout the belt as well as

proximal to the known deposits.

The Project has several walk-up targets that could provide immediate upside to the current

mineral resource. These include the newly acquired New Manitoba Cu -Ni historical occurrence

and the untested EM conductors between New Manitoba and the Mayville Cu -Ni Deposit

approximately 10 km to the west. As well, the newly acquired Page and Ore Fault deposits and

their potential extensions are also priority targets. The Company plans to complete an initial drill

program to test these priority targets later this year and will provide further details on the targets

and timing as soon as possible.

The other deposits and mineral occurrence in the MM Project area are:

• The New Manitoba deposit, which has a historical mineral resource estimate of 1.8Mt at

0.75% Cu and 0.33% Ni (Manitoba Mineral Inventory Card #217) (Note: The Company has

not been able to verify the historical estimate as relevant and the historical estimate

should not be relied on);

• The Ore Fault deposit, containing a previously NI 43-101 reported indicated resource of

0.9Mt at 0.32% Ni and 0.24% Cu and an inferred resource of 2.5Mt 0.35% Ni and 0.19%

(Ewert et al., 2009; see reference 1, below); and,

• The Page deposit, containing a previously NI 43-101 reported indicated resource of 1.5Mt

at 0.32% Ni and 0.13% Cu (Ewert et al., 2009).

(Note that all previous mineral resource estimates mentioned above need to be updated

following the CIM 2019 Best Practice Guidelines to make them current)

The Ore Fault and Page deposit MREs were prepared in accordance with National Instrument 43-

101. The Company considers these estimates to be reasonable but has not independently verified

them and will be required to take additional steps including drilling to complete the verification

process.

Mineral Resource Estimate

The updated mineral resource estimate for the MM Project is provided in Tables 1 and 2, below.

The new estimate was prepared by Micon International Ltd. ( ‘Micon’) following the CIM 2019

Best Practice Guidelines and is reported in accordance with National Instrument 43-101 (“NI 43-

101”) - Standards of Disclosure for Mineral Projects and its Companion Policy 43 -101CP. The

current mineral resource was estimated by Micon using an updated drill hole database and new

mineralization wireframes that capture all verified historical drill hole data sets. Block grade

interpolation was performed using the Kriging technique). The resource modeling was completed

by Micon in accordance with both CIM Guidelines and the relevant parts of the JORC 2012 Code,

and in keeping with regulatory requirements for the filing of technical reports for mineral

resource estimates at both the TSX Venture Exchange and the Australian Stock Exchange (ASX).

The Technical Report incorporating the new resource estimate will be accessible on SEDAR

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

Table 1A. Mayville Pit Constrained and Underground Resource as of December 31, 2023

Mining Category Tonnage Density CuEq Cu Ni Co Pd Pt Au SR

% % % % g/t g/t g/t

OP Indicated 32,019,000 3.00 0.61 0.40 0.16 0.01 0.13 0.05 0.05

3.17

Inferred - - - - - - - - -

UG

Indicated 322,461 3.00 1.62 0.96 0.37 0.02 0.19 0.08 0.11

NA

Inferred 203,323 3.00 1.50 0.96 0.32 0.02 0.16 0.08 0.11

*SR = strip ratio

Table 1B. Makwa Pit Constrained and Underground Resources as of December 31, 2023

Mining Category Zone Tonnage Density NiEq Ni Cu Co Pd Pt SR

% % % % g/t g/t

OP

Indicated

HG1 4,846,590 2.94 1.26 0.89 0.17 0.03 0.71 0.19

4.66

LG1 9,370,784 2.88 0.48 0.28 0.08 0.01 0.19 0.06

HG1 +

LG1 14,217,374 2.90 0.75 0.48 0.11 0.02 0.37 0.10

Inferred LG1 18,000 2.88 0.36 0.23 0.04 0.01 0.11 0.04

UG

Indicated

HG1 437,743 2.94 1.19 0.83 0.11 0.03 0.73 0.21

NA LG1 62,783 2.88 0.53 0.30 0.08 0.01 0.27 0.08

HG1 +

LG1 500,526 2.93 1.11 0.77 0.11 0.02 0.67 0.19

Inferred HG1 +

LG1 - - - - - - - -

*SR = strip ratio

Notes to Accompany the Makwa and Mayville Resource Estimate:

1. The effective date of this Mineral Resource Estimate is December 31, 2023.

2. The MRE presented above uses economic assumptions for both surface mining and underground mining.

3. The MRE has been classified in the Indicated and Inferred categories following spatial grade continuity analysis and geological

confidence.

4. The calculated cut-off grades to report the MRE are dynamic in nature following metallurgical recovery curves, the average

COG for Makwa is 0.30 % Ni in surface mining and 0.84 % Ni in underground mining ; for Mayville is 0.30 % Cu in surface

mining and 1.37 % Cu in underground mining.

5. The economic parameters used metal prices of US$9.0/lb Ni, US$3.75/lb Cu, US$23.0/lb Co, US$900/oz Pt, US$1,400/oz Pd

and US$1,750/Au with specific metallurgical recovery curves summarized as follow: copper recoveries of 87% to high grade

copper concentrate of 28%; and nickel recoveries in the range from 50% to 68% to 10% nickel concentrate at Mayville and

50-68% nickel recovery to 10% nickel concentrate based on average grades and over 70% recovery for highest grade (+1% Ni)

blocks at Makwa) ; a mining cost of US$3.5/t in surface and US$80.0/t in underground ; Processing cost of US$15/t and a

General & Administration cost of US$3.2/t.

6. For surface mining the open pits at Makwa and Mayville use a slope angle of 53°.

7. The block models for Makwa and Mayville are rotated and use a block size of 10 m x 5 m x 5 m with the narrow side s across

strike (North-South) and vertically (z direction).

8. The open pit optimization uses a re-blocked size of 10 m x 10 m x 10 m and for the underground the optimization uses stopes 20

m long by 20 m high and a minimum mining width of 3 m.

9. Messrs. Alan J. San Martin, MAusIMM(CP) and Charley Murahwi, P.Geo. , FAusIMM, from Micon International Limited are the

Qualified Persons (QPs) for this Mineral Resource Estimate (MRE).

10. Mineral resources unlike mineral reserves do not have demonstrated economic viability. The estimate of mineral resources may

be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.

11. The mineral resources have been estimated in accordance with the CIM Best Practice Guidelines (2019) and the CIM Definition

Standards (2014).

12. Totals may not add correctly due to rounding.

13. Equivalent (Eq) Grade Calculations: (a) Makwa NiEq = Ni% + ((Cu% x CuR x CuP) + (Co% x CoR x CoP) + (Pt g/t x PtR x PtP) + (Pd g/t

x PdR x PdP))/(NiR x NiP); (b) Mayville CuEq* = Cu% + ((Ni% x NiR x NiP) + (Co% x CoR x CoP) + (Pt g/t x PtR x PtP) + (Pd g/t x PdR

x PdP) + (Au g/t x AuR x AuP))/(CuR x CuP). NiEQ = nickel equivalent grade. R = metal recovery. P = metal price.

14. The Mayville CuEq calculation assumes the production of separate Cu and Ni concentrates.

15. Metallurgical recovery ranges using input grades at the cutoff grade (low end) and 2 times the average open pit resource grade

(high end) are as follow: Makwa: Ni: 36 to 86%; Cu: 85.6% (invariant); Co: fixed to nickel recoveries; Pd: 59 to 90% (capped); Pt:

39 to 90% (capped); Mayville: For the copper concentrate model :Cu: 86.5 to 86.9%; Ni: 5% (fixed); Co: (5% - fixed to nickel

recovery); Pd: 42% (fixed); Pt: 35% (fixed); Co: 30% (fixed); For the nickel concentrate model: Cu: 5% (fixed); Ni: 42 to 69%;C o:

matches nickel recoveries; Pd: 33%; Pt: 21%; Au: 10%.

Table 2. Contained Metal Values for the Open Pit Resources at the Makwa and Mayville

Properties (Indicated Category only)

Deposit CuEq NiEq Cu Ni Co Pd Pt Au

(t) (t) (t) (t) (t) koz koz koz

Mayville 195,316 - 128,076 51,230 3,202 134 51 51

Makwa - 106,630 15,639 68,243 2,843 169 46 -

Combined 195,316 106,630 143,715 119,474 6,045 303 97 51

Deposit CuEq NiEq Cu Ni Co Pd Pt Au

lbs lbs lbs lbs lbs oz oz oz

Mayville 430,597,339 - 282,358,911 112,943,564 7,058,973 133,826 51,472 51,472

Makwa - 235,079,303 34,478,298 150,450,754 6,268,781 169,127 45,710 -

Combined 430,597,339 235,079,303 316,837,209 263,394,318 13,327,754 302,953 97,182 51,472

In summary, the updated open -pit resource estimate for the Mayville deposit includes 32.0

million tonnes in the indicated category with 0.40% Cu and 0.16% Ni and byproduct

concentrations of cobalt, palladium, platinum and gold (0.61% copper equivalent grade). The

open pit resources at Makwa include 14.2 million tonnes in the indicated category with 0.48% Ni,

0.11% Cu, 0.02% Co, 0.37 g/t Pd and 0.10 g/t Pt (0.75% nickel equivalent grade). The Makwa

deposit is subdivided into a central, higher-grade zone (‘HG1’) and a flanking (both hanging-wall

and footwall) lower-grade (‘LG1’) zone. The new resource estimate includes 4.8 million tonnes

of the HG1 zone grading 0.89% Ni (1.26% nickel equivalent grade).

The previous resource estimate for the MM Project was published by RPA Inc. (2014) and

supported a Preliminary Economic Assessment based on two open pit mines feeding a central

concentrator to be located at the Mayville property. Low base metal prices during the period of

2014 to 2020 precluded any significant new development activity and drilling at the Project.

However, with an improved outlook for copper prices and the increasing strategic importance of

nickel as a critical metal, the Project ranks favourably for future exploration and development.

Compared to the previous published resource estimate for the MM project (RPA Inc., 2014), the

combined open pit resources (indicated category) increased by 12.4 million tonnes or 36.8%. This

increase is largely attributable to the inclusion of recent infill drilling (Makwa – 2022), improved

metallurgical recoveries from testwork completed after the previous resource estimate was

published, and a more favourable US dollar to Canadian dollar exchange rate.

Mayville Deposit

The Mayville magmatic sulfide deposit is a copper -rich disseminated sulfide deposit hosted by

the western part of the ~17 km long late Archean Mayville mafic -ultramafic complex. The

Mayville deposit is approximately 1.5 km long, up to 200 metres wide, and has been delineated

to maximum depth of ~500 metres. It dips steeply to the south. The deposit includes the Main

Zone (Figure 2, below) and two satellite zones (not shown here) located at the eastern end of the

deposit. The two satellite zones have not been included in the current resource estimate.

The mineralization in the Mayville deposit occurs principally as disseminations of chalcopyrite

and pyrrhotite with lesser pentlandite and pyrite hosted in what has been described as an

intrusive breccia unit emplaced near the base of the Mayville Complex.

Figure 2. Mayville Long Section (looking north) showing drill hole traces and mineralization block

model

A sectional view of the mineralization block model is shown in Figure 3 below.

Figure 3: Representative cross section for the Mayville deposit , looking west, and showing the

current Micon block model coded to copper grade and selected length-weighted average drill hole

intersections for drill holes captured on this section.

Main one

M

11.1m . 4 Cu

. 4 Ni

M

4.3m . 1 Cu

. 4 Ni

M 11

1 . m .8 Cu

.43 Ni

M

. m . 3 Cu

. 4 Ni

M 1

.4m 1. 1 Cu

.38 Ni