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Highland Copper Announces Positive Feasibility Study Results FOR Its Copperwood Project IN Michigan - IRR of 18% After Tax, Capital Cost of $275 M and an Average Payable Copper Production of 61.7 M Lbs PER Year

Economic Studies

NEWS RELEASE

HIGHLAND COPPER ANNOUNCES POSITIVE FEASIBILITY STUDY RESULTS

FOR ITS COPPERWOOD PROJECT IN MICHIGAN -

IRR OF 18% AFTER TAX, CAPITAL COST OF $275 M AND AN AVERAGE PAYABLE

COPPER PRODUCTION OF 61.7 M LBS PER YEAR

Longueuil, Canada, June 15, 2018. Highland Copper Company Inc. (TSXV: HI; OTCQB: HDRSF)

(“Highland” or the “Company ”) is pleased to announce the results of a feasibility study (the

“Feasibility Study”) for its 100%-owned Copperwood project located in Gogebic County, in the

Western Upper Peninsula of Michigan, U.S.A. (the “Copperwood Project”).

Highlights of the Copperwood Project Feasibility Study

(All amounts in this news release are in US dollars, unless otherwise indicated. Due to rounding, numbers presented

throughout this release may not add up precisely to the totals provided.)

• After-tax internal rate of return (“IRR”) of 18%

• Initial capital expenditures of $245 million, net of pre-production revenue of $30 million

• Life-of-mine (“LOM”) cash costs of $1.53/lb, including royalties and $1.29/lb in the first

five years of production

• Proven and Probable Reserves of 25.4 M tonnes @ 1.43% Cu and 3.83 g/t Ag, containing

801.8 M lbs of copper and 3.1 M oz of silver

• Additional Mineral Resources of 49.9 M tonnes @ 1.15 % Cu and 3.42 g/t Ag in the Inferred

category, containing 1.3 B lbs of copper and 5.5 M oz of silver using a 1% Cu cut-off

• Average annual LOM payable copper production of 61.7 M lbs and 100,570 oz of silver

• Initial copper production expected in early 2021

“A major step forward for the Copperwood Project” said Denis Miville-Deschênes, President and

CEO of Highland Copper. “The Feasibility Study demonstrate s the significant potential of this

project located in a great historic mining jurisdiction. Based on the results of the study, we can now

focus on putting in place a comprehensive financing package.” He added “The development of a

mine at Copperwood represents a tremendous opportunity to create hundreds of jobs in the region.”

The Feasibility Study was conducted by, and under the supervision of, G Mining Services Inc.

(“GMSI”) in collaboration with SGS Canada Inc. (Lakefield), Lycopodium Minerals Canada Ltd,

Golder Associates and Foth Infrastructure and Environment. The s tudy provides a comprehensive

overview of the Copperwood Project and defines an economically feasible, technically and

environmentally sound project.

Opportunities to Increase Copperwood Project Value

Highland and its consultants have identified a number of opportunities to increase the value of the

Copperwood Project. T hese include upgrading inferred mineral resources , i ncreasing mine

productivity utilizing innovative continuous mining technologies , conducting further geotechnical

studies to optimize ore recovery and minimize mining dilution , reviewing tailings disposal

alternatives, and conducting additional testing to maximize metallurgical recoveries.

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Copperwood Project

The Copperwood Project property is located, by road, approximately 22.5 km to the north of

Wakefield and 40 km from the town of Ironwood, both in Gogebic County, w estern Upper

Peninsula, Michigan. The project area is at the south edge of the Keweenaw Copper province and

underlain by c lastic sediments of the Oronto Group, including the Copper Harbor, Nonesuch and

Freda Formations.

The Copperwood and its “s atellite” deposits are hosted by the limbs of the northwe st dipping

Presque Isle Syncline within the Nonesuch Formation. The Nonesuch Formation contains two

mineralized sequences, one located at the base, the Lower Copper Bearing Sequence (“LCBS”) and

a stratigraphically higher one, the Upper Copper Bearing Sequence (“UCBS”), separated by poorly

mineralized sediments with a variable thickness of 0.5 m to 6.0 m.

Chalcocite is the only copper sulfide bearing mineral, occurring principally as disseminations within

shale and siltstone. Individual disseminated grains of chalcocite are most commonly very fine grain,

approximately 5 to 50 microns in diameter. The Copperwood deposit is relatively sub- horizontal

with a thickness that varies from 1.6 m to 3.7 m.

Mineral Resources

GMSI prepared a Mineral Resource estimate for the Copperwood Project based on data provided up

to and including April 12, 2018. The resource estimate was prepared in accordance with CIM

Standards on Mineral Resources and Reserves (adopted May 10, 2014) and is reported in accordance

with National Instrument 43 -101 (“ NI 43-101”) Standards of Disclosure for Mineral Projects .

Classification, or assigning a level of confidence to Mineral Resources, has been undertaken with

strict adherence to CIM Standards on Mineral Resources and Reserves. In the opinion of GMSI, the

resource evaluation reported herein is a reasonable representation of the global Mineral Resources

found at the Copperwood Project at the current level and spacing of sampling.

The mineral estimate was prepared under the supervis ion of Réjean Sirois, P. Eng. of GMSI, an

independent “qualified person” as defined in NI 43-101. Geovia GEMS™ and Leapfrog Geo™

software were used to facilitate the resource estimation process.

Total Measured and Indicated Mineral Resources of the Copperw ood deposit are reported at

49.3 million tonnes grading an average of 1.54% Cu and 3.76 g/t Ag, containing 1.68 billion pounds

of copper and 5.9 million ounces of silver using a cut-off grade of 1.0% Cu for the combined LCBS

and UCBS. Inferred Mineral Reso urces are reported at 1.6 million tonnes grading an average of

1.18% Cu and 1.55 g/t Ag, containing 43 million pounds of copper and 0.1 million ounces of silver

using a cut-off grade of 1.0% Cu.

Total Inferred Mineral Resources located in the satellite deposits are reported at 49.9 million tonnes

grading 1.15% Cu and 3.42 g/t Ag, containing 1.27 billion pounds of copper and 5.5 million ounces

of silver using a cut-off grade of 1.0% Cu for the combined LCBS and UCBS.

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Mineral Resource Estimate

1.0% Cu Cut-off Grade – April 30th, 2018

Deposits

Resource

Category

Tonnage

(M t)

Copper

Grade

(%)

Silver

Grade

(g/t)

Copper

Contained

(M lbs)

Silver

Contained

(M oz)

LCBS

Measured 27.3 1.68 4.58 1,009 4.0

Indicated 14.9 1.46 2.47 479 1.2

M + I 42.2 1.60 3.84 1,488 5.2

Inferred 1.6 1.18 1.55 43 0.1

UCBS

Measured - - - - -

Indicated 7.1 1.21 3.26 189 0.7

M + I 7.1 1.21 3.26 189 0.7

Inferred - - - - -

Satellite LCBS Inferred 34.4 1.17 2.29 888 2.5

Satellite UCBS Inferred 15.5 1.12 5.92 384 3.0

Notes on Mineral Resources:

1) Mineral Resources are reported using a copper price of $3.00/lb and a silver price of $18/oz.

2) A payable rate of 96.5% for copper and 90% for silver was assumed.

3) The Copperwood Feasibility Study reported metallurgical testing with recovery of 86% for copper and 73.5% for

silver.

4) Cut-off grade of 1.0% copper was used, based on an underground “room and pillar” mining scenario.

5) Operating costs are based on a processing plant located at the Copperwood site.

6) Assuming a $3.00/lb Cu price, a sliding scale 3.0% NSR royalty on the Copperwood Project is payable to

leaseholders. Assuming closing of the acquisition of the White Pine Project, a 3% NSR royalty on the Copperwood

Project payable to Osisko Gold Royalties Ltd. is reduced to a 1.5% NSR royalty.

7) Measured, Indicated and Inferred Mineral Resources have a drill hole spacing of 175 m, 250 m and 350 m,

respectively.

8) No mining dilution and mining loss were considered for the Mineral Resources.

9) Rock bulk densities are based on rock types.

10) Classification of Mineral Resources conforms to CIM definitions.

11) The qualified person for the estimate is Réjean Sirois, P.Eng., Vice President Geology and Resources for GMSI.

The estimate has an effective date of 30th April 2018.

12) Mineral Resources that are not mineral reserves do not have demonstrated economic viability. The estimate of

Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, sociopolitical,

marketing, or other relevant issues.

13) LCBS: Lower Copper Bearing Sequence.

14) UCBS: Upper Copper Bearing Sequence.

15) The quantity and grade of reported Inferred Resources in this estimation are uncertain in nature and there has been

insufficient exploration to define these Inferred Resources as Indicated or Measured Mineral Resources.

Mineral Reserves

The Mineral Reserves estimate was prepared by Carl Michaud, P. Eng. of GMSI, in accordance with

the CIM Standards on Miner al Resources and Miner al Reserves. Mineral Reserves are based on

Measured and Indicated Mineral Resources dated April 30, 2018 and do not include Inferred Mineral

Resources. Measured and Indicated Mineral Resources are inclusive of Proven and Probable

Reserves.

The Proven and Probable Reserves stated below were estimated based on these unconstrained

Measured and Indicated Resources, noted above and the work carried out for the Feasibility Study.

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Mineral Reserve Estimate

Reserve by Category Tonnes

(M t)

Cu

Grade

(%)

Ag

Grade

(g/t)

Cu

contained

(M lbs)

Ag

contained

(M oz)

Proven 17.5 1.50 4.43 579.6 2.5

Probable 7.9 1.28 2.50 222.2 0.6

Proven & Probable 25.4 1.43 3.83 801.8 3.1

Notes:

1) The Mineral Reserves were estimated using the Canadian Institute of Mining, Metallurgy and Petroleum (CIM)

Standards for Mineral Resources and Reserves, Definitions and Guidelines prepared by the CIM Standing

Committee on Reserve Definitions and adopted by CIM Council May 10th, 2014.

2) Mineral Reserves are estimated at a cut -off grade of 1% Cu. The cut -off will vary depending on the economic

context and the operating parameters.

3) Mineral Reserves are estimated using a long-term copper price of $3.00/lb and a silver price of $16.00/oz.

4) Assuming a $3.00/lb Cu price, a sliding scale 3.0% NSR royalty on the Copperwood Project is payable to

leaseholders. Assuming closing of the acquisition of the White Pine Project, a 3% NSR royalty on the Copperwood

Project payable to Osisko Gold Royalties Ltd. is reduced to a 1.5% NSR royalty.

5) Mineral Reserves are estimated using an ore loss of 3%, a dilution of 0.1 m for the floor and a 0.25 m for the back

of the stope and the development.

6) The economic viability of the mineral reserve has been demonstrated.

7) A minimum mining height of 2.1 m was used.

8) The copper recovery was estimated at 86%.

9) The qualified person for the estimate is Carl Michaud, P. Eng., Underground Engineering Manager for GMSI. The

estimate has an effective date of May 25, 2018

10) The number of metric tonnes was rounded to the nearest thousand. Any discrepancies in the totals are due to

rounding effects; rounding followed the recommendations in NI 43-101.

Mine Operations and Services

It is proposed to mine the deposit with a conventional highly mechanized, drill and blast room-and-

pillar mining method. The method consists of the extraction of a series of entries and cross -cuts in

the ore, leaving pillars in place to support the back. The entries, cross cuts and pillars have been

sized using geotechnical analysis of the local host rocks, and experience from other mines sharing

similar ground conditions.

The mine will be accessed via covered box -cut to establish a portal at the mine entrance from the

surface, located at the central -west part of the deposit. The mine c onsists of two mining sectors:

West and East. The western part, being higher grade with a thicker mineralized zone, will be mined

in priority.

The mine is split into panels, which consist of at least 12 rooms that provide multiple headings where

all activities of the mining cycle can be done in parallel to achieve high productivities , as opposed

to activities in series as is the case in a single heading. The mining cycle consists of drilling ,

explosives loading and blasting, mucking, scaling and bolting.

Mining operations are planned with two 10-hour shifts per day, 360 days per year to achieve a

production target of 2.4 M tonnes per year, or 6,600 tonnes per day . To achieve this production, a

total of 7 to 9 panels must be in production at any given time.

The mining operation begins with drilling of the working face , which is accomplished with two -

boom hydraulic-electric jumbo drills. Each round is drilled 4.25 m (14 ft) in length with an effective

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break of 4.00 m. The rooms are 6.1 m wide with a height tha t varies according to the ore column

thickness. The height dimension dictates the productivity, which varies from panel to panel.

Mucking will be done with 10 tonnes load-haul-dump (“LHD”) units that will load muck at the mine

face and transport it to the conveyor loading point established for the production panel. The LHD

performance will be a function of dip of the stope and distance. The conveyor loading points will be

regularly moved as production advances in the panel to be less than 250 m from the headings.

Scaling of the rooms is planned with a smaller low -profile LHD unit equipped with a scaling arm

that rubs the roof to remove any loose rocks.

Bolting will be done by a mechanized bolter to install roof support and wall bolts. In the stopes,

1.8 m rebar bolts are required on a 1.2 m by 1.2 m pattern with wire mesh. In addition, 1.8 m friction

bolts are planned in the pillars (i.e. walls) on a 1.5 m by 1.5 m pattern with wire mesh. At room

intersection rebar bolt length is increased to 2.4 m.

Ventilation for the mine will be provided by a 400 m3/s fresh air raise and two exhaust raises at the

eastern and western end of the mine. The dewatering system will consist of six pumping stations

capable of evacuating 2,220 l/min of underground water inflow and mine water.

Highland continues to study the use of tailings as back- fill in the open stopes . If this approach is

selected, it would provide cost savings for tailing disposal and closure costs.

Life-of-Mine (LOM) Metal Production

The LOM production for the Copperwood Project is shown below. Payable c opper production is

estimated at 300,000 tonnes (660 million pounds) with an annual average of 28,000 tonnes (61.7

million pounds) over the 10.7- year mine life which includes a 3 -month commissioning and ramp-

up period. The average payable rate is 95.8% which includes a 0.2% concentrate loss. Payable silver

production over the LOM is 1.10 million ounces with an annual average of 101 thousand ounces of

silver.

Production Physicals Total

Concentrate k of dmt 1,264

Cu con. Grade % Cu 24.7

Cu metal production M lbs 690

Ag metal production k oz 2,296

Cu payable metal M lbs 660

Ag payable metal k oz 1,077

Processing and Metallurgy

The process plant design for the project is based on a metallurgical flowsheet designed to produce

copper concentrate with a nominal throughput of 6,600 tpd and a planned availability of 91.3%.

The flowsheet consists of semi -autogenous grinding in closed circuit with a ball mill targeting a

primary grind of 40 microns, rougher flotation with concentrate regrind, cleaner flotation using three

stages of cleaning, concentrate thickening, filtration and tailings disposal.

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The primary observation of variabilit y testwork showed that the copper recovery varies from 77%

up to ~ 90% with a concentrate grade from 20% up to 29% Cu. The overall average copper recovery

is 86% with a weighted average copper concentrate grade of 24.7%. Studies show that copper

recovery might be further increased by concentrate grade and reagents optimization.

Studies are underway to evaluate the optimal destination and transport option for the Copperwood

concentrate.

Environment and Permitting

Environmental baseline studies were done for the Copperwood Project from late 2008 through the

spring of 2011. These studies were used to identify existing and historical conditions in the P roject

area and select potential siting of infrastructures based on an environmental management and permit

approvals perspective.

An Environmental Impact Assessment was prepared to comply with the State of Michigan

requirements of Part 632 of Act No. 451 of the Public Acts of 1994 as amended. This document

outlines the baseline monitoring and studies conducted for the Copperwood Project including the

natural, social, economic, cultural, and historical aspects of the environment that may be potentially

impacted by the Project design.

In order to construct and operate the Copperwood P roject, a number of permits m ust be obtained

and agreed upon between Highland and environmental regulatory agencies on both the state and

federal levels. Highland maintain s an open and proactive approach with both state and federal

regulators.

The major environmental permits required to develop the Copperwood Project include: Part 632

Non-Ferrous Metallic Mining Permit; Part 31 National Pollutant Discharge Elimination System

Permit; Part 55 Air Permit to Install; Part 301 Inland Lakes and Streams Permit; Part 303 Wetland

Permit; Part 315 Dam Safety Permit; Part 325 Great Lakes Submerged Lands Permit; and Section

10 US Army Corps of Engineers Water Intake Permit.

Highland has filed amendment requests, renewals or new applications (as applicable) for these

permits and expects to have all required permits by the fall of 2018.

Power and Surface Infrastructure

The Company is considering a 40 km 115 kV powerline supplied by a well -implemented energy

provider in the state of Michigan. Detailed engineering will begin in the coming months for the best

routing to minimize the impact on the environment. County Road 519 will be upgraded under the

responsibility of the Michigan Department of Transportation.

Capital and Operating Costs

The initial capital costs, including all direct a nd indirect cos ts, are estimated at $275 million,

including a contingency of $22.9 million . Pre-production revenue of $30.35 million reduces the

capital expenditures to $244.6 million.

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Initial Capital Expenditure Summary

Initial CAPEX ($M)

General 1.150

Infrastructure 36.650

Power & Electrical 5.156

Water & TDF Mgmt. 22.875

Mobile Equipment 27.240

Mine Infrastructure 53.529

Process Plant 45.771

Construction Indirects 27.609

General Services & Owner's Costs 22.251

Pre-Production, Commissioning 9.838

Sub-Total Before Contingency 252.069

Contingency 9.1% 22.899

Total Incl. Contingency 274.968

Less: Pre-Production Revenue (30.348)

Total Incl. Contingency & Pre-Prod. Revenue 244.619

Operating costs include mining, processing, G&A services, concentrate transportation and

concentrate treatment and refining charges. The concentrate transportation, treatment charges and

refining are deducted from gross revenues to calculate the net smelter return (“NSR”). The NSR for

the Project during operations is estimated at $1.821 million , excluding $30.35 million of NSR

generated during pre -production and presented as a reduction of initial capital expenditures. The

average NSR over the LOM is $2.80 per pound of payable copper. The average operating cost over

the LOM is $39.84 per tonne of ore or $1.53 per pound of payable copper with mining representing

53.4% of the total operating costs, or $21.26 per tonne of ore.

Sustaining Capital Expenditure Summary

The total LOM sustaining capital is estimated at $156.5 million.

Sustaining Capital LOM

($M)

Tailings disposal facility expansion 28.45

Water treatment plant 6.13

Mine equipment purchases 43.69

Mine development expenditures 78.21

Total Sustaining Capital 156.47

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Operating Costs Summary

Operating Cash Flow LOM $/t ore $/lb Cu

Payable ($M)

Cu Revenue 2,047 81.92 3.15

Ag Credits 17 0.67 0.03

Revenue 2,064 82.59 3.17

Concentrate Transportation Costs 94 3.75 0.14

Treatment & Refining Charges 149 5.96 0.23

Net Smelter Return 1,821 72.88 2.80

Royalties 85 3.39 0.13

Mining Costs 531 21.26 0.82

Processing Costs 308 12.31 0.47

G&A Costs 72 2.88 0.11

Total OPEX (incl. royalties) 996 39.84 1.53

Operating Cash Flow 826 33.03 1.27

Note: Ore tonnage and payable copper unit costs excluding commissioning period.

Sensitivity Analysis

Variance

After-Tax Results

NPV 0%

($M)

NPV 8%

($M)

IRR

(%)

Payback

(yrs)

Metal Price Sensitivities

20% 655.1 318.8 31.9% 2.1

10% 486.1 218.1 25.3% 2.5

0% 316.0 116.8 18.0% 3.2

-10% 145.6 15.4 9.5% 5.2

-20% -31.8 -89.2 0.0% 10.5

Initial Capital Cost Sensitivities

20% 266.1 70.2 13.2% 3.9

10% 290.8 93.3 15.4% 3.5

0% 316.0 116.8 18.0% 3.2

-10% 341.4 140.4 21.1% 2.8

-20% 366.8 164.0 24.7% 2.5

Operating Cost Sensitivities

20% 150.7 22.8 10.3% 4.2

10% 233.5 69.8 14.4% 3.6

0% 316.0 116.8 18.0% 3.2

-10% 398.6 163.9 21.3% 2.9

-20% 481.2 210.9 24.3% 2.6