Mr Tyrwhitt joined the Board as an Independent Non-Executive Director in October 2019.

Mr Tyrwhitt has three decades of senior leadership experience in the global engineering and construction sectors. Mr Tyrwhitt was the Group CEO of Dubai Financial Market (DFM)-listed construction firm Arabtec Holdings from 2016 to 2019. In addition to his position as CEO of Arabtec Holding, he also held the position of Group CEO of Nasdaq Dubai-listed, interior solutions firm Depa Group, from 2016 to 2019.

Mr Tyrwhitt has served on the board as an Executive Director of Depa Limited; as a Non-Executive Director of Design Studio Group Limited, a Singapore based subsidiary of Depa Group listed on the Singapore Stock Exchange; and as a Non-Executive Director of Jordan Wood Industries PSC, a listed Jordanian company which manufactures office and household furniture.

Previous to his roles at Depa Group and Arabtec Holdings, he held the position of CEO at Asia Resource Minerals Plc, an Indonesian coal mining company listed in London.

Previous to this, Mr Tyrwhitt worked for more than 25 years with Leighton Group, now CIMIC, where he served as Group CEO from 2011 to 2014. From 2007 to 2011, Mr Tyrwhitt oversaw Leighton’s Asian operations as the Managing Director for Leighton Asia, from the Leighton’s Asian headquarters in Hong Kong.

Mr Tyrwhitt is a fellow of the Australian Academy of Technological Sciences and Engineering, a fellow of the Institution of Engineers Australia, a member of the Hong Kong Institute of Engineers and a member of the College of Civil Engineers, Australia.

Mr Tyrwhitt is a member of the Audit & Risk Committee, Remuneration Committee, Nomination Committee and Tender Review Committee.

Mr Finnegan holds a Bachelor of Science (Mining) with 24 years’ experience in the mining industry. The last 15 years have primarily been spent in senior line management positions. Mr Finnegan has a strong commercial and technical background and has spent time in operations on the east and west coast of Australia as well as a number of countries throughout Asia.

Mr Gibbs joined the Board as a Non-Executive Director in July 2023.

Mr Gibbs is a mining engineer with 40 years of international experience in large-scale mining operations with copper and gold, diamonds, uranium, coal (thermal and coke), talc and nickel laterite resources. His experience includes both underground and open pit mining across South Africa, Namibia, Papua New Guinea, Australia, Thailand, and Indonesia. He has held positions in the areas of feasibility study management, mine planning, operations, productivity improvement and cost reduction, research and due diligence, strategic planning, and project evaluation and development.

Mr Gibbs is a Director of PT Amman Mineral Internasional Tbk, a gold and copper producer listed on the Indonesia Stock Exchange.

Mr Gibbs holds a BSc Hons degree in mining engineering, Mine Manager Certificate  First Class for Western Australia and a Mine Manager Certificate from South Africa.  He is a Fellow of The Royal School of Mines (ARSM) and a Chartered Engineer (C Eng).

Ms McComish joined the Board as an Independent Non-Executive Director in March 2021. She is also a Non-Executive Director at ASX listed Webjet Limited and not for profits Beyond Blue and Chief Executive Women.

Ms McComish was a Partner with KPMG Australia for 30 years, and served as a National Board Member and National Mining Leader. She has extensive audit and advisory experience including governance and risk, capital transactions and regulatory filings with national and global companies. Ms McComish has international experience across multiple sectors, principally in energy and natural resources, financial services and infrastructure.

Ms McComish is a Member of the Australian Takeovers Panel, and Chair of the Advisory Board for the School of Business and Law at Edith Cowan University. She is also a Fellow of Chartered Accountants Australia and New Zealand and a Member of the Australian Institute of Company Directors. Ms McComish was awarded an honorary Doctorate of Business from Edith Cowan University and in 2018, she was recognised in the Top 100 Global Inspirational Women in Mining.

Mr Finnegan holds a Bachelor of Science (Mining) with 24 years’ experience in the mining industry. The last 15 years have primarily been spent in senior line management positions. Mr Finnegan has a strong commercial and technical background and has spent time in operations on the east and west coast of Australia as well as a number of countries throughout Asia.

Mrs Lummis holds a Bachelor of Commerce (Honours) in Accounting, Auditing and Tax. Mrs Lummis joined Macmahon in 2018 as Group Financial Controller and was appointed Chief Financial Officer on 1 November, 2021.

Prior to Macmahon, Mrs Lummis has more than 20 years’ experience with KPMG South Africa and KPMG Australia providing services to a large number of global listed companies in the mining and mining services sectors.

Donald is a Fellow Chartered Accountant with extensive financial and corporate experience in high value private and listed public companies in the mining and industrial services sectors. He has held strategic key executive leadership positions and non-executive director roles in developing and operational entities, within which he has demonstrated a strong focus on delivering high return business outcomes.

Over the past 20 years, Donald has been a member of group executive leadership teams in ASX 200 companies, with specific accountability in roles including Chief Executive – Investments, Chief Operating Officer and Group Chief Financial Officer. With over 27 years of experience, Donald brings financial, strategic, commercial, and operational expertise to the team.

Elizabeth Gray holds a Graduate Diploma in Occupational Health and Safety and a Bachelor of Nursing. Ms Gray has 20 years of experience in the mining industry in health, safety, environment, training, and community engagement. She has been instrumental in implementing strategies to generate positive HSEQ performance and drive cultural change. Before Macmahon, Ms Gray held senior management positions with Peabody Australia, Sandvik, and BHP (BMA) Daunia Mine.

Nicola Hamilton holds a Bachelor of Human Resource Management (honours). She has more than 20 years of experience in people management with global resources companies, including PTTEP, Beach Energy and Schlumberger. She specialises in building and leading HR functions in diverse climates and cultures with expertise in business and strategic planning, change management, talent management and development, and employee relations.

Maha is a senior executive and qualified lawyer with extensive national and international experience across legal, commercial, governance, and risk in various sectors including resources, infrastructure, mining and commodities, engineering, oil and gas, and construction.

Maha has significant experience advising on large-scale project developments and disputes.  She is also skilled in managing and documenting complex transactions and commercial contracts.

Maha holds a Master of Laws, a Bachelor of Laws (Honours), and a Bachelor of Science. She joined Macmahon in 2021 and was appointed as General Counsel in January 2022.  She has authored several published, peer reviewed academic papers and articles.