Trevali Reports Preliminary Q2-2018 Production of 104 Million Payable Pounds of Zinc and Operating Costs of US$58 Per Tonne

VANCOUVER, British Columbia, July 18, 2018 -- Trevali Mining Corporation (“Trevali” or the “Company”) (TSX:TV) (OTCQX:TREVF) (Frankfurt:4TI) reports preliminary consolidated second quarter 2018 (“Q2-2018”) production of 103.9 million payable pounds of zinc, 10.5 million payable pounds of lead and 337,801 payable ounces of silver (Table 1). The Company remains firmly on track with its 2018 consolidated annual production guidance of 400-427 million payable pounds of zinc.

Q2 Highlights:

• On track with 2018 annual zinc production guidance of 400-427 million payable pounds
• Preliminary consolidated operating costs of US$58 per tonne
• Operating costs within or below guidance at all operations; on track with 2018 consolidated operating cost guidance of US$60-$66 per tonne
• Continued strong performance at Perkoa
• Santander back at normal capacity following mill maintenance in the first quarter
• Caribou improved performance following winter seasonal effect in the first quarter
• Normal concentrate shipping schedules realized at all operations

“As per plan, we saw increased zinc production in the second quarter and the Company remains on track to achieve annual production and cost guidance,” stated Dr. Mark Cruise, Trevali’s President and CEO. “The overall improvements, versus the first quarter, reflect continued strong performance at Perkoa, a return to normal capacity at Santander and decreasing seasonal effects at Caribou. Unfortunately, Rosh Pinah had a challenging quarter, however we anticipate significant improvement in the second half of the year as we focus on optimizing operations, specifically underground mining efficiency and productivity.”

Perkoa Mine, Burkina Faso
Preliminary Q2-2018 production was 46.2 million pounds (20,940 tonnes) of payable zinc with an average zinc recovery of 93% (Table 2). Mine output and mill throughput for the quarter were 182,551 tonnes and 176,027 tonnes of ore, respectively. Given the strong performance over the first half of 2018, the Company is increasing 2018 zinc production guidance by 9 million pounds (4,080 tonnes) to 164-174 million payable pounds (74,400-78,950 tonnes).

Table 2: Perkoa Preliminary Q2-2018 Production

Rosh Pinah Mine, Namibia
Preliminary Q2-2018 production was 20.8 million pounds (9,449 tonnes) of payable zinc, 2.1 million pounds (974 tonnes) of payable lead and 28,388 ounces of payable silver (Table 3). Mine output and mill throughput for the quarter was 159,797 tonnes and 173,082 tonnes, respectively.

Performance for the quarter was below expectation; specifically, mine production did not achieve targeted levels due to non-optimal operational practices. Consequently, 2018 production guidance has been reduced by 10 million pounds (4,540 tonnes) to 95-105 million payable pounds (43,100-47,640 tonnes) of zinc. The Company is actively addressing this issue and continues to onboard key skills, advance workforce training, provide operational support and implement compliance tracking.

Table 3: Rosh Pinah Preliminary Q2-2018 Production

Caribou Mine, Canada
Preliminary Q2-2018 production was 20.5 million pounds (9,315 tonnes) of payable zinc, 6.5 million pounds (2,937 tonnes) of payable lead and 178,753 ounces of payable silver (Table 4). Mine production for the quarter was 266,500 tonnes, an operational record, and mill throughput was 247,222 tonnes. As expected, the winter impacts experienced in the first quarter decreased in the second quarter, which positively impacted zinc recoveries.

Table 4: Caribou Preliminary Q2-2018 Production

Santander Mine, Peru
Preliminary Q2-2018 production was 16.4 million pounds (7,434 tonnes) of payable zinc, 1.9 million pounds (867 tonnes) of payable lead and 130,659 ounces of payable silver (Table 5). Recoveries averaged 89% for zinc, 79% for lead and 61% for silver.

The mill maintenance was completed prior to the beginning of the second quarter, resulting in mill throughput of 223,884 tonnes (an operational record) and mine output of 198,318 tonnes for the quarter.

The Santander mill is now operating at approximately 2,500 tonnes-per-day, which is above design capacity, and as such the Company is increasing 2018 zinc production guidance by 1 million pounds (500 tonnes) to 55-58 million payable pounds (24,950-26,320 tonnes).

Table 5: Santander Preliminary Q2-2018 Production

Q2-2018 PRELIMINARY OPERATING COSTS AND ANNUAL COST GUIDANCE ^{(1, 2, 3)}

Table 6: Q2-2018 Preliminary Operating Costs and Annual Cost Guidance (US$ per tonne)

⁽¹⁾ Constitutes forward-looking information; see “Cautionary Note Regarding Forward-Looking Statements”.
⁽²⁾ Trevali’s ownership interest is 90% of Perkoa and 90% of Rosh Pinah.
⁽³⁾ Costs are preliminary and subject to adjustment.

2018 CONSOLIDATED PRODUCTION GUIDANCE
Production guidance for the year remains unchanged at between 400 and 427 million pounds (181,500-193,700 tonnes) of payable zinc, 43.8 and 46.0 million pounds (19,900-20,900 tonnes) of payable lead and 1.40 and 1.47 million ounces of payable silver (Table 7).

The Company is increasing its zinc production guidance at Perkoa and Santander by an aggregate of 10 million pounds (4,540 tonnes) of payable zinc, which offsets the lower zinc production guidance at Rosh Pinah of 10 million pounds (4,540 tonnes). There will be moderate fluctuations on a quarter-to-quarter basis due to normal-course mine scheduling (Figure 1).

Table 7: 2018 Consolidated Production Guidance ^(1&2)

⁽¹⁾ Constitutes forward-looking information; see “Cautionary Note Regarding Forward-Looking Statements”.
⁽²⁾ Trevali’s ownership interest is 90% of Perkoa and 90% of Rosh Pinah.

CONCENTRATE SHIPPING AND SALES
Normal shipping schedules were realized at all operations in the second quarter and there were no material inventory backlogs that affected concentrate sales.

STRENGTHENED MANAGEMENT TEAM
Trevali has added two new key management positions:

Vice President, General Counsel and Corporate Secretary
Steven Molnar has joined Trevali as Vice President, General Counsel and Corporate Secretary. He joins the Company from McCarthy Tétrault LLP, where he practiced corporate and securities law with a focus on the mining industry. He brings extensive experience in corporate governance and continuous disclosure requirements, public and private mergers and acquisitions and capital markets transactions, and joint ventures and other commercial arrangements in the mining industry. Steve will be overseeing all legal aspects at Trevali, providing advice on strategic direction, planned initiatives, operations and corporate governance and regulatory compliance.

Vice President, Mineral Resource Management
Yan Bourassa has joined Trevali as Vice President, Mineral Resource Management. He joins the Company with extensive experience in resource estimation / disclosure and has a solid background in operations and exploration. Yan will be overseeing the development and maintenance of the individual resource and reserve models for all Trevali mining assets combined with the management of all in-mine conversion drilling, drill data management, and sampling QA/QC. He will also be developing frameworks for mineral resource management, supervising and training geologists and providing technical guidance to Senior Management team as part of due diligence processes.

Additionally, Trevali has implemented operation-level changes to reinforce ongoing improvement and optimization initiatives at all operations.

Qualified Person and Quality Control/Quality Assurance
EurGeol Dr. Mark D. Cruise, Trevali's President and CEO, is a qualified person as defined by NI 43-101, has supervised the preparation of, and has verified the scientific and technical information that forms the basis for this news release. Dr. Cruise is not independent of the Company as he is an officer, director and shareholder.

ABOUT TREVALI MINING CORPORATION
Trevali is a zinc-focused, base metals company with four mines: the wholly-owned Santander mine in Peru, the wholly-owned Caribou mine in the Bathurst Mining Camp of northern New Brunswick, its 90% owned Rosh Pinah mine in Namibia and its 90% owned Perkoa mine in Burkina Faso.

The shares of Trevali are listed on the TSX (symbol TV), the OTCQX (symbol TREVF), the Lima Stock Exchange (symbol TV), and the Frankfurt Exchange (symbol 4TI). For further details on Trevali, readers are referred to the Company’s website (www.trevali.com) and to Canadian regulatory filings on SEDAR at www.sedar.com.

On Behalf of the Board of Directors of
TREVALI MINING CORPORATION
“Mark D. Cruise” (signed)
Mark D. Cruise, President

Contact Information:
Steve Stakiw, Vice President - Investor Relations and Corporate Communications
Email: sstakiw@trevali.com
Phone: (604) 488-1661 / Direct: (604) 638-5623

Cautionary Note Regarding Forward-Looking Statements
This news release contains “forward-looking information” within the meaning of the Canadian securities legislation and “forward-looking statements” within the meaning of Section 27A of the United States Securities Act of 1933, as amended, Section 21E of the United States Exchange Act of 1934, as amended, the United States Private Securities Litigation Reform Act of 1995, or in releases made by the United States Securities and Exchange Commission, all as may be amended from time. Statements containing forward-looking information express, as at the date of this news release, the Company’s plans, estimates, forecasts, projections, expectations, or beliefs as to future events or results. Such forward-looking statements and information include, but are not limited to statements as to: the timing and amount of estimated future production; the estimation of mineral resources and mineral reserves; costs and timing of development; operating efficiencies, including the ability to manage water while reducing power consumption, costs and expenditures; expectations regarding milling operations and metal production shortfalls; metal output and throughput rates; cost guidance and anticipated annual results; anticipated results of future exploration; and forecast future metal prices.

These statements reflect the Company’s current views with respect to future events and are necessarily based upon a number of assumptions and estimates that, while considered reasonable by the Company, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. If any assumptions are untrue, it could cause actual results, performance or achievements to be materially different from future results, performance or achievements expressed or implied by such statements. Assumptions have been made regarding, among other things, present and future business strategies and the environment in which the Company will operate in the future, including commodity prices, anticipated costs and ability to achieve goals.

Forward-looking statements are subject to known and unknown risks, uncertainties and other important factors that may cause the Company’s actual results, level of activity, performance or achievements to be materially different from those expressed or implied by such forward-looking statements, including but not limited to: risks related to joint venture operations; fluctuations in spot and forward markets for silver, zinc, base metals and certain other commodities (such as natural gas, fuel oil and electricity); fluctuations in currency markets; risks related to the technological and operational nature of the Company’s business; changes in national and local government, legislation, taxation, controls or regulations and political or economic developments in Canada, the United States, Peru, Namibia, Burkina Faso, or other countries where the Company may carry on business in the future; risks and hazards associated with the business of mineral exploration, development and mining (including environmental hazards, industrial accidents, unusual or unexpected geological or structural formations, pressures, cave-ins and flooding); risks relating to the credit worthiness or financial condition of suppliers, refiners and other parties with whom the Company does business; inadequate insurance, or inability to obtain insurance, to cover these risks and hazards; employee relations; relationships with and claims by local communities and indigenous populations; availability and increasing costs associated with mining inputs and labour; the speculative nature of mineral exploration and development, including the risks of obtaining necessary licenses and permits and the presence of laws and regulations that may impose restrictions on mining; diminishing quantities or grades of Mineral Resources as properties are mined; global financial conditions; business opportunities that may be presented to, or pursued by, the Company; the Company’s ability to complete and successfully integrate acquisitions and to mitigate other business combination risks; challenges to, or difficulty in maintaining, the Company’s title to properties and continued ownership thereof; the actual results of current exploration activities, conclusions of economic evaluations, and changes in project parameters to deal with unanticipated economic or other factors; increased competition in the mining industry for properties, equipment, qualified personnel, and their costs, as well as other risks as more fully described in the Company’s annual information form for the year ended December 31, 2017, which is available on the Company’s website (www.trevali.com) and filed under our profile on SEDAR (www.sedar.com). Investors are cautioned against attributing undue certainty or reliance on forward-looking statements. Although the Company has attempted to identify important factors that could cause actual results to differ materially, there may be other factors that cause results not to be as anticipated, estimated, described or intended. The Company does not intend, and does not assume any obligation, to update these forward-looking statements or information to reflect changes in assumptions or changes in circumstances or any other events affecting such statements or information, other than as required by applicable law.

Note to United States Investors

In accordance with applicable Canadian securities regulatory requirements, all mineral resource estimates of the Company disclosed or incorporated by reference in this news release have been prepared in accordance with Canadian National Instrument 43-101 - Standards of Disclosure for Mineral Projects, classified in accordance with Canadian Institute of Mining Metallurgy and Petroleum's “CIM Standards on Mineral Resources and Reserves Definitions and Guidelines”.

The Company uses the terms "measured mineral resources", "indicated mineral resources" and "inferred mineral resources". While these terms are recognized by Canadian securities regulatory authorities, they are not recognized by the United States Securities and Exchange Commission. US investors are cautioned not to assume that any part or all of the material in these categories will ever be converted into reserves.

A photo accompanying this announcement is available at http://www.globenewswire.com/NewsRoom/AttachmentNg/9055296f-a55b-49c2-bd7d-610806906aab