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Trilogy Metals Announces Pre-Feasibility Study Results and Reserves for the Arctic Project, Alaska

Economic Studies

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News Release

Trilogy Metals Announces Pre-Feasibility Study Results

and Reserves for the Arctic Project, Alaska

February 20, 2018 - Vancouver, British Columbia – Trilogy Metals Inc. (TSX/NYSE

American: TMQ) (“Trilogy Metals” or the “Company”) is pleased to announce the positive

results of its Pre-Feasibility Study (“PFS”) for its Arctic Copper-Zinc-Lead-Silver-Gold Project

(“Arctic” or the “Arctic Project”) in the Ambler mining district of Northwestern Alaska. These

results convert indicated mineral resources at Arctic to probable mineral reserves. All amounts

are stated in U.S. dollars unless otherwise stated.

Trilogy Metals will host a conference call on February 21, 2018

at 11:00am (Pacific Time) or 2:00pm (Eastern Time) to discuss these

results. Call-in information is provided at the end of this news release and

on our website at www.trilogymetals.com.

Highlights of the Arctic PFS study are as follows:

 Pre-tax Net Present Value (“NPV”)8% of $1,935.2 million calculated at the beginning of

the three-year construction period and an Internal Rate of Return (“IRR”) of 38.0% for

the base case.

 After-tax NPV8% of $1,412.7 million and after-tax IRR of 33.4% for the base case.

 Initial capital expenditure of $779.6 million and sustaining capital of $65.9 million for

total estimated capital expenditures of $845.5 million over the estimated 12-year mine

life. In addition, closure and reclamation costs are estimated at $65.3 million.

 Estimated pre-tax and after-tax payback of initial capital within 2 years. At $2.00/lb

copper, after-tax payback is 3 years.

 Minimum 12-year mine life supporting a maximum 10,000 tonne-per-day conventional

grinding mill-and-flotation circuit to produce copper, zinc and lead concentrates

containing significant gold and silver by-products.

 Life of mine strip ratio of 6.9 to 1.

 Average annual payable production projected to be more than 159 million pounds of

copper, 199 million pounds of zinc, 33 million pounds of lead, 30,600 ounces of gold

and 3.3 million ounces of silver for life of mine.

 A capital intensity ratio on initial capital of approximately $6,200 per tonne of average

annual copper equivalent produced.

 Estimated cash costs of $0.15/lb of paya ble copper (C1 cash costs include on-site

mining and processing costs, road tolls and maintenance, transport, royalties, and is

net of by-product credits).

 Total “all-in” cash costs (initial/sustaining capital, operating, transportation, treatment

and refining charges, road toll, and by-product metal credits) estimated at $0.63/lb of

payable copper.

 Economic indicators justify moving forward with permitting and a feasibility study.

TSX/NYSE American

Symbol: TMQ

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The PFS was prepared under National Inst rument 43-101 standards by independent

consultant, Ausenco Engineering Canada Inc. (“Ausenco”) of Vancouver, Canada and the full

technical report will be filed on SEDAR and EDGAR within 45 days of this news release. The

Company also engaged Amec Foster Wheeler (“ Amec”) to complete mine planning and SRK

Consulting (Canada) Inc. (“SRK”) to complete tailings and waste design, hydrology and water

management studies.

The PFS for the Arctic Project describes the po tential technical and economic viability of

establishing a conventional open-pit copper-zinc-lead-silver-gold mine-and-mill complex for a

10,000 tonne-per-day operation. The base case scenario utilizes long-term metal prices

of $3.00/lb for copper, $1.10/lb for zinc, $1.00/lb for lead, $18.00/oz for silver and

$1,300/oz for gold. The PFS was prepared on a 100% ownership basis.

“The results of the PFS show that Arctic is a robust, high quality project. We are very pleased

with the improvements in the economics in this Pre-Feasibility Study compared with the

Preliminary Economic Assessment (“PEA”) perf ormed on the Arctic Project in 2013. The

increase in net present value of Arctic in the PFS from the PEA is due to a number of cumulative

factors, including: 1) improved mine plan that moves approximately $100 million in the pre-

stripping forward which allows for a more aggressive mine ramp up – two years, rather than

four years in the PEA. This brings forward a significant amount of metal production and

cashflow; 2) use of LNG versus diesel in the PEA – this redu ces power generation costs and

saves approximately $2.00/tonne in operating costs on processing; 3) improved tax legislation

in the United States improves after-tax NPV and IRR; 4) improved long term commodity prices,

specifically for copper and zinc; 5) improved metallurgical recoveries; and 6) an almost 20%

increase in resource tonnes along with an improvement in grade resulting from our in-fill

drilling programs conducted over the past co uple of years”, said Rick Van Nieuwenhuyse,

President and Chief Executive Of ficer. “We are also very excited with the potential for job

opportunities for the Upper Kobuk region. The PFS estimate s approximately 400 year round

jobs during mine operations. This is import ant for our local communities in the Kobuk and

Koyukuk regions that currently have limited opportunities for long term employment.”

Rick Van Nieuwenhuyse continues, “The Arctic Project is now set to advance to the next stages

of development: Permitting and Feasibility. With the average grade currently mined in open

pit copper mines approaching 0.5% worldwide, we are blessed with a truly high-grade copper

project in Arctic with grades of 5% copper equivalent1. Based on the foregoing, I expect Arctic

could be among the highest grade open pit copper mines in the world if and when it is placed

into production. And with Public Scoping now completed on the Ambler Mining District

Industrial Access Project (“AMDIAP”) and the Draft EIS underway, and with continued support

from Governor Walker and the St ate of Alaska as outlined in his recent State of the State

address (Walker State of the State Address), we are starting to see all the pieces come together

to realize the value inherent in developing the Ambler Mining District – one of the highest grade

volcanogenic massive sulfide di stricts known in the world. Meanwhile, we will of course

continue to explore our Bornite Project with a $10 million program funded by South32, which

we hope to advance towards a developmen t decision. With the long-term demand

fundamentals for copper driven by increased use of alternative forms of energy and a transition

from internal combustion engines to non-pollut ing electric vehicles, both of which require 5

times the amount of copper than carbon based fuels, we expect the price of copper to remain

strong over the long term – especially when we consider the impending supply crunch expected

by analysts.”

1. See Table 9.

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Arctic Pre-Feasibility Study – Mining and Processing

The PFS is based on a conventional truck-and-sho vel, open-pit mine design at a single pit,

10,000 tonne-per-day mining and milling operation with sulphi de floatation concentration

resulting in the production of copper, zinc and lead concentrates. Based on the pre-feasibility

level metallurgical work on the sulphide minera lization, the average recoveries are projected

to be 90.0% for copper, 91.7% for zinc and 80.0% for lead. The majority of the silver and gold

report to the lead concentrate at 95% payable. The mineralized material at the Arctic Project

will be processed through conven tional milling and flotation for an estimated mine life of 12

years. The PFS contemplates the metallurgical flow sheet to consist of a conventional mill with

a talc pre-float followed by a bulk copper-lead flotation and zinc flotation followed by a

separation of the copper and lead. Most of the precious metals will report to the copper and

lead concentrates. Key parameters and assump tions used for the PFS study are discussed

below and summarized in Tables 1 through 3.

Table 1 – Mining rates and volumes of mined material

Type of Mining Total Years

Avg

Tonnes/yr

(000’s)

Avg

Tonnes/day

Total

Tonnes

(000’s)

Open-pit mineralized material (Years 0

– 12)

12 3,586.5 9,826 43,038

Open-pit waste (Years 0 – 12) 12 24,756 67,824 297,071

Total material mined 340,109

Average strip ratio for the life of mine 6.9:1

Table 2 – Projected payable metal production

Metal Total Payable Production

Average Annual

Production

Life of Mine

lbs (000’s) Tonnes lbs (000’s) Tonnes

Copper 1,908,493 865,687 159,041 72,141

Zinc 2,399,128 1,088,237 199,927 90,686

Lead 405,727 184,037 33,811 15,336

Ounces Ounces

Silver 40,237,644 3,353,137

Gold 367,531 30,628

Table 3 – Base case head grades, recoveries, metal prices, and other data

Head Grades

Copper % 2.32

Zinc % 3.24

Lead % 0.57

Silver g/t 36.0

Gold g/t 0.49

Metal Recoveries

To Copper Concentrate

- Copper % 90.0

- Silver % 11.8

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- Gold % 35.0

To Zinc Concentrate

- Zinc % 91.7

To Lead Concentrate

- Lead % 80.0

- Silver % 61.1

- Gold % 49.7

Payables

Payable Copper % 90.0

Payable Zinc % 91.7

Payable Lead % 80.0

Table 3 Continued – Base case head grades, recoveries, metal prices, and other data

Concentrate grades - Copper

Copper % 30.3

Silver g/t 169

Concentrate grades - Zinc

Zinc % 59.2

Concentrate grades - Lead

Lead % 55.0

Silver g/t 2,383

Gold g/t 34.0

Metal Prices

Copper $/lb 3.00

Zinc $/lb 1.10

Lead $/lb 1.00

Silver $/oz 18.00

Gold $/oz 1,300

Other Parameters

Life of mine Years 12

LNG price $/GJ LHV 18.45

Electrical power – LNG $/kWhr 0.17

NANA NSR % Net Revenues 1.0

Arctic Pre-Feasibility Study – Project Economics

The results of a discounted cash flow analysis for the Project are presented in Table 4 below.

NPV, IRR and payback values are estimated for both pre-tax and after-tax scenarios. The base

case scenario utilizes the long-term metals prices outlined in Table 3 and a discount rate of

8%. IRR and NPV values are calculated to show sensitivities for a range of copper prices from

$2.00 to $4.00 and zinc prices from $0.90 to $1.30.

Under the Exploration Agreement and Option to Lease (“NANA Agreement”) between Trilogy

Metals and NANA Regional Corporation, Inc. (“NANA”), NANA has the right, following a

construction decision, to elect to purchase a 16% to 25% direct interest in the Arctic Project

or, alternatively, to receive a 15% Net Proceeds Royalty. This PFS was carried out on a 100%

ownership basis and does not include the impact on Trilogy Metals if NANA elects to purchase

an interest in the Arctic Project under the NA NA Agreement or, alternat ively, the impact on

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Trilogy Metals and the Project if the NPR becomes applicable. The PFS does include the 1.0%

Net Smelter Royalty (“NSR”) to be granted to NANA under the NANA Agreement in exchange

for a surface use agreement.

Under the Option Agreement (“ South32 Option Agreement”) between Trilogy Metals and

affiliates of South32 Limited (“South32”), South32 has the right to form a 50/50 Joint Venture

with respect to the Company’s Alaskan assets including the Company’s Arctic Project. Upon

exercise of the option, the Company will transfer its Alaskan assets, including the Arctic Project,

and South32 will contribute a minimum of $150 million, to a newly formed joint venture. For

more information on the South32 Option Agreement see the Company’s press release on April

10, 2017 (https://Trilogy PR April 10 2017). This PFS was carried out on a 100% ownership

basis and does not include the impact on Trilog y Metals if South32 elects to form the joint

venture under the Option Agreement.

Additional information on the NANA Agreement and the South32 Option Agreement is included

in the Company’s 2017 Annual Report on Form 10-K, which is available on SEDAR and EDGAR.

Table 4a – Pre-tax discounted cash flow estimates for varying copper prices

Pre-Tax NPV*

($ million)

Copper Price

($/lb)

2.00 2.50

Base

Case

3.00 3.50 4.00

Discount

Rates

5% 1,437.8 2,039.9 2,642.0 3,244.0 3,846.1

Base Case 8% 993.4 1,464.3 1,935.2 2,406.1 2,877.0

10% 770.0 1,173.4 1,576.8 1,980.1 2,383.4

IRR % 25.3 31.9 38.0 43.6 48.9

Payback Years 2.9 2.3 1.9 1.6 1.4

*Assumes base case metals prices of $1.10/lb zinc, $1.00/lb lead, $18.00/oz silver and $1,300/oz gold

Table 4b - After-tax discounted cash flow estimates for varying copper prices

After-Tax NPV*

($ million)

Copper Price

($/lb)

2.00 2.50

Base

Case

3.00 3.50 4.00

Discount

Rates

5% 1,064.6 1,512.4 1,946.1 2,377.2 2,808.5

Base Case 8% 718.2 1,071.5 1,412.7 1,751.5 2,090.5

10% 543.7 848.1 1,141.5 1,432.7 1,724.1

IRR % 22.3 28.1 33.4 38.2 42.8

Payback Years 3.0 2.4 2.0 1.8 1.5

*Assumes base case metals prices of $1.10/lb zinc, $1.00/lb lead, $18.00/oz silver and $1,300/oz gold

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Table 4c – Pre-tax discounted cash flow estimates for varying zinc prices

Pre-Tax NPV*

($ million)

Zinc Price

($/lb)

0.90 1.00

Base

Case

1.10 1.20 1.30

Discount

Rates

5% 2,340.1 2,491.0 2,642.0 2,792.9 2,943.8

Base Case 8% 1,699.6 1,817.4 1,935.2 2,053.0 2,170.8

10% 1,375.2 1,476.0 1,576.8 1,677.5 1,778.3

IRR % 35.1 36.5 38.0 39.4 40.8

Payback Years 2.1 2.0 1.9 1.8 1.8

*Assumes base case metals prices of $3.00/lb copper, $1.00/lb lead, $18.00/oz silver and $1,300/oz gold

Table 4d - After-tax discounted cash flow estimates for varying zinc prices

After-Tax NPV*

($ million)

Zinc Price

($/lb)

0.90 1.00

Base

Case

1.10 1.20 1.30

Discount

Rates

5% 1,726.2 1,836.2 1,946.1 2,056.1 2,166.1

Base Case 8% 1,240.3 1,326.5 1,412.7 1,498.9 1,585.1

10% 993.5 1,067.5 1,141.5 1,215.5 1,289.5

IRR % 30.8 32.1 33.4 34.6 35.8

Payback Years 2.2 2.1 2.0 1.9 1.9

*Assumes base case metals prices of $3.00/lb copper, $1.00/lb lead, $18.00/oz silver and $1,300/oz gold

As seen in Table 5, average life of mine cash costs for the Arctic Project, which include on-

site operating costs, treatment and refinement charges, transportation , road toll charges,

royalties and by-product credits (zinc, lead, silver and gold), are estimated to be $0.15/lb of

payable copper. If the total capi tal costs (initial plus sustaining and closure costs) of $910.8

million are included, then the total “all-in” cash cost is estimated to be $0.63/lb of payable

copper.

Table 5 – Summary of estimated cash costs

Cash Costs

($/lb Cu payable)

Average Life of

Mine

C1 (delivered metal – net of by-product credits) 0.15

Total Cash Costs (opex, TC/RCs, capex, sustaining capex, closure) 0.63

This PFS was developed on the basis of up-to-date macro-economic and technical assumptions

related to the Arctic Project and supersedes the previous Preliminary Economic Assessment

completed for the Arctic Project in 2013.

Arctic Pre-Feasibility Study - Capital Costs

The PFS estimates the initial de velopment capital expenditure at $779.6 million during the

proposed two and a half-year construction peri od. With sustaining (deferred and working)

capital over the life of the mine estimated at $65.9 million, the expected total capital

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investment is expected to be $845.5 million over the estimated 12-year mine life. In addition,

closure costs are estimated to be $65.3 million. The capital cost estimates, which are shown

in Table 6, generally comply with AACEI Class 4 level esti mates and are based on budget

quotations and the consultants database/experie nce with similar projects and should not be

considered definitive.

Table 6 – Capital estimate summary

Initial Capital Estimate

($ million)

Mine 281.2

Crushing 18.3

Process 113.8

Tailings 30.3

On Site Infrastructure 84.5

Off Site Infrastructure 15.6

Subtotal – Direct costs 543.7

Indirect Costs 121.9

Owners Costs 22.0

Contingency 92.0

Initial development capital 779.6

Sustaining Capital Estimate

($ million)

Mining Equipment 45.1

Tailings 19.9

G&A 0.9

Total sustaining capital 65.9

Total capital expenditure for the life of mine 845.5

 Rounding as required by reporting guidelines may result in apparent summation differences

Infrastructure

The Arctic Project will require 12.6 MW of average load for 10,000 tonne-per-day operation

demand. Power will be generated by six 4.4 MW LNG generators, housed in a common

building. Four units will be in service with the fifth unit reserved for stand-by capacity and the

sixth unit reserved for maintenance. Onsite power costs using LNG are estimated to be

$0.17/kWh, assuming a LNG price of $18.45/GJ LHV.

There is currently no developed surface access to the Arctic Project area and beyond. Access

to the Arctic Project is proposed to be vi a the AMDIAP, a road approximately 340 km (211

miles) long, extending west from the Dalton Highway where it would connect with the proposed

Arctic Project area. The final terminal for the road has not yet been determined. Although the

capital costs of the road are not yet final, an estimate of approximately $300 million has been

used in this PFS. The Alaska Industrial Development and Export Authority (“AIDEA”) is

currently permitting the AMDIAP. Although Trilogy has been in discussions with AIDEA about

investigating alternatives to reduce the overall cost to construct the AMDIAP, the final cost of

the road could be higher than $300 million. The working assumption of this PFS study is that

AIDEA would arrange financing in the form of a public-private partnership and arrange for the

construction and maintenance of the access road. AIDEA would charge a toll to multiple mining

and industrial users (inc luding the Arctic Project) in order to pay back the costs of financing

the AMDIAP. This model is very similar to what AIDEA undertook when the DeLong Mountain

Transportation System (also known as the Re d Dog Mine Road and Port facilities) was

constructed in the 1980s. The amount paid in tolls by any user will be affected by the cost of

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the road, its financing structure, and the number of mines and other users of the road which

could also include commercial transportation of materials and consumer items that would use

the AMDIAP to ship concentrates to the Port of Anchorage in Alaska and possibly provide goods

and commercial materials to villages in the region.

For the purposes of this PFS study, AIDEA and Trilogy Metals reviewed current bonding ability

of AIDEA based on a $300 million 30-year bond with a rate of 6.00% compounded semi-

annually and a $300 million 15-year bond with a rate of 5.50% compounded semi-annually.

Although the final toll payments will be negotiated with AIDEA and any Public-Private

Partnership owners of the access road sometime in the future, it has been assumed that a toll

would be paid based on the Arctic Project paying approximately $9.7 million each year for its

12-year mine life. The toll payments are assume d to commence in Year 1 of production and

are an operating cost in the Ar ctic PFS. In addition, a road maintenance fee of $2.00/tonne

processed has been assumed.

Operating Costs

The Project is projected to produce approxim ately 159 million pounds of payable copper per

year at an estimated average C1 cash operat ing cost of $0.15/lb Cu over the estimated 12-

year mine life. These estimated cash costs are net of zinc, lead, gold and silver byproducts and

include onsite operating costs, transport, road tolling, smelting an d refining charges and

royalties. Maintenance parts and repairs are estimated based on industry standard factors for

these costs. Mining costs are estimated at $3.09 per tonne of material mined, at a strip ratio

of 6.9 which equates to $20.47 per tonne of ma terial processed. Deta ils of the estimated

operating costs, and other charges, are presented in Tables 7 and 8 below.

Table 7 – Operating costs

Estimated Operating Cost

(as indicated)

Mining $/tonne processed 20.47

Processing $/tonne processed 15.09

General and Administrative $/tonne processed 5.60

Plant Services $/tonne processed 0.95

Road Toll and Maintenance $/tonne processed 4.70

Total on-site operating costs $/tonne processed 46.81

 Rounding as required by reporting guidelines may result in apparent summation differences

Table 8 – Concentrate transportation, treatment and refining charges

Estimated Operating Cost

(as indicated)

Concentrate Transportation charges $/dmt concentrate 270.37

Treatment charges - Copper $/dmt concentrate 80.00

Treatment charges – Zinc $/dmt concentrate 200.00

Treatment charges - Lead $/dmt concentrate 180.00

Refinement charges - Copper $/ lb of payable copper 0.08

 dmt: dry metric tonne

Mineral Resource Estimate

The mineral resource estimate, as seen in Table 9 and which formed the basis of the PFS, has

been prepared by Bruce M. Davi s, FAusIMM, BD Resource Consulting, Inc., and Robert Sim,