Tertiary Minerals Names Lorenz Werndle as Non-Executive Director, Succeeding 25-Year Board Veteran Donald McAlister

Donald McAlister Ends 25-Year Tenure on Tertiary Minerals Board

Donald McAlister will retire as non-executive director of Tertiary Minerals plc on 4 August 2026, concluding an exceptional 25-year service since the Company’s initial AIM Market listing. His departure, attributed to other full-time work commitments, represents a significant governance milestone for the company. The transition is planned and orderly, reflecting no adverse circumstances.

Chairman Patrick Cheetham praised Mr. McAlister’s extensive industry expertise and invaluable counsel, noting his role as a key advisor since the Company's AIM admission. McAlister’s exit marks a pivotal moment in governance, with comprehensive succession planning in place.

Lorenz Werndle Strengthens Board with Mining and Financial Expertise

At 51 years old, Lorenz Werndle joins Tertiary Minerals plc bringing deep experience in finance, mining, and corporate development. He currently serves as Chief Financial Officer and Executive Director of Kavango Resources plc, an LSE-listed exploration and development firm active in Botswana and Zimbabwe. This role equips him with relevant expertise managing capital-intensive mineral exploration projects in southern Africa, aligning with Tertiary’s Zambian operations.

Previously, Mr. Werndle was CFO of Nasdaq-listed Blue Gold Limited and held leadership roles at Mwana Africa Plc, Lonrho Plc, and Ambrian Plc. His extensive background in mining strategy, corporate development, and mergers and acquisitions across Africa and globally positions him as a fitting successor to Mr. McAlister, offering valuable insight into the geopolitical and operational environments of Tertiary’s projects.

Board Committee Roles Assigned to New Non-Executive Director

Upon appointment, Lorenz Werndle will chair the Audit and Risk Committee, succeeding Donald McAlister. This role entails critical oversight of financial reporting, risk management, and internal audit functions. His finance and mining sector expertise is expected to enhance scrutiny of the Company’s financial controls as exploration advances in Zambia and Nevada.

Additionally, Mr. Werndle will serve on the Nomination and Remuneration Committees, influencing board composition, executive pay, and succession planning. He will stand for election at the 2027 Annual General Meeting, consistent with Tertiary Minerals’ Articles of Association and AIM governance best practices, allowing shareholders to approve his appointment.

Strategic Director Appointment Supports Zambia and Nevada Exploration Initiatives

Lorenz Werndle’s appointment aligns with Tertiary Minerals plc’s focus on copper and precious metal exploration in Nevada and Zambia. He expressed enthusiasm for the Company’s "exciting portfolio in Zambia and Nevada with real potential," underscoring the Board’s intent to strengthen sector and regional expertise during project development.

Chairman Patrick Cheetham emphasized the value of Mr. Werndle’s African experience, stating it will be "invaluable as we continue the exploration of our exciting Zambian exploration projects." This highlights the Company’s strategic emphasis on energy transition metals and the importance of enhanced governance in navigating regulatory and geopolitical challenges in Zambia. The Company’s diversified assets position it well within the global shift toward decarbonisation and renewable energy infrastructure.

AIM Governance Compliance and Shareholder Election Process

Tertiary Minerals plc disclosed Lorenz Werndle’s appointment in line with AIM Rules for Companies (Rule 17 and Schedule Two paragraph (g)). Mr. Werndle is 51 years old and currently holds directorships at Kavango Resources plc and Tala Services Ltd. No other directorships or partnerships within the past five years require disclosure, confirming a clean regulatory record.

Mr. Werndle holds no shares, warrants, or options in Tertiary Minerals plc, supporting his status as an independent non-executive director. The Company confirmed no further disclosures are required under AIM rules. Shareholders will have the opportunity to formally elect him at the 2027 AGM, adhering to standard governance procedures.

Tertiary Minerals’ Market Position in Mineral Exploration

Tertiary Minerals plc is an AIM-listed mineral exploration and development company strategically positioned to benefit from rising demand for energy transition metals such as copper and cobalt. Its portfolio spans projects in Zambia and Nevada, combining exposure to a stable, mining-friendly North American jurisdiction with an emerging African mining frontier.

The Company highlights the political stability and geological potential of its project locations. Nevada is a globally recognized mining hub with established regulatory frameworks, while Zambia represents a growing exploration frontier backed by government support. The appointment of a director with southern African expertise reflects management’s focus on enhancing regional knowledge to advance projects and engage stakeholders effectively.

Immediate Appointment and Transition Timeline

Lorenz Werndle’s appointment took effect on 27 July 2026, ensuring seamless board oversight. Donald McAlister will formally depart on 4 August 2026, allowing an eight-day overlap for knowledge transfer and continuity of Audit and Risk Committee responsibilities. This arrangement minimizes governance disruption.

The formal shareholder election of Mr. Werndle at the 2027 AGM completes the appointment process, consistent with AIM governance standards. No extraordinary shareholder meetings or interim votes are planned, indicating adherence to routine succession protocols.

Advisory and Broker Support for Governance Transition

SP Angel Corporate Finance LLP serves as Tertiary Minerals plc’s Nominated Adviser and Broker, assisting with this governance transition. Contacts Caroline Rowe and Jen Clarke provide further information. The Nominated Adviser’s role includes ensuring compliance with AIM Rules and governance best practices during board changes.

AlbR Capital Limited acts as Joint Broker, with Lucy Williams and Duncan Vasey as contacts. Managing Director Richard Belcher also serves as a Company liaison. This multi-channel communication approach supports transparent investor relations during the board transition.

Inside Information Disclosure and Regulatory Compliance

The announcement is classified as inside information under the Market Abuse Regulation (EU) No. 596/2014, retained in UK law post-Brexit. Tertiary Minerals plc determined that appointing a non-executive director with significant sector experience constitutes material information likely to influence investor decisions.

Disclosure via Regulatory Information Service channels ensures simultaneous public access, fulfilling market abuse prevention obligations. This transparent communication underscores the Company’s commitment to regulatory compliance and investor transparency regarding key corporate developments.