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AIM HZM 137.50 GBX
Developing the next major nickel project in Brazil

Senior Management

Our management team have extensive experience in the exploration and mining sector, demonstrating strength and diversity.


Simon Retter
Company Secretary and Chief Financial OfficerBSc (hons), ACA.
Mr Retter has extensive experience in the public markets and the mining sector, specifically, reverse takeovers, IPOs and secondary fundraising. Starting his career at Deloitte and Touche LLP where he qualified as a chartered accountant, moving on to work for a number of London listed exploration and mining companies with overseas operations.

Guy de Freitas
Head of Business Development
Guy is an experienced mining finance professional, with an extensive track record in private equity and investment banking, and has over US$2.0 billion of completed transaction experience across IPOs, follow-ons, M&A, project financing and principal investments, across a range of commodities and geographies. Prior to joining Horizonte, Guy worked for Appian Capital Advisory LLP and Macquarie Capital. Guy has significant experience in Brazil having played a lead role while at Appian in managing the firm’s Brazilian portfolio, which included the successful development of the Serrote copper-gold mine. Guy holds a Masters in Finance from INSEAD and Bachelor of Business Science (Finance) from the University of Cape Town.

Katie Millar
Head of ESG & CommunicationsMBA, BA, PG Dip.
Ms Millar is a corporate responsibility specialist with extensive social development, licensing & policy experience. Ms Millar possesses an MBA from IE Business School, a Post-Graduate Diploma from Queensland University of Technology and a Bachelor of Arts majoring in Political Science from the University of Queensland. Her experience includes working for the Australian Government (Federal & State), Anglo American Plc Metallurgical Coal and Anglo American Plc Base Metals Brazil. Ms Millar possesses knowledge in working across the IFC Performance Standards, Equator Principles, Global Reporting Initiative, CONAMA Resoluções (Brazil) & ISO 14001. She also demonstrates knowledge in working across large capital projects, industrial operations and public policy. Ms Millar is fluent in Portuguese and has worked in Brazil for over 7 years.

Anthony Finch
Studies ManagerB Eng (Min), B Econ, MAusIMM (CPMin), P Eng. (APEGBC).
Mr Finch is a professional mining engineer who has over thirty years’ experience in mining engineering, mining operations management and mining consulting. Mr Finch`s mining operations career ranges from production engineer to mine manager. Additionally, Mr Finch has provided technical mining engineering consulting services throughout the world on a broad range of underground and surface mines and commodities. Mr Finch has lead and participated in many mining studies from scoping to full feasibility in a variety of commodities, jurisdictions, and mining methods. He possesses competencies in mine planning, mine design and scheduling, economic evaluation, mine management, mine optimisation, due diligence, audits, mergers and acquisitions, project management, technology development, and business consulting. Mr Finch is a competent and qualified person in most commodities, in most jurisdictions, and most mining methods and has published papers on mine optimisation and mining technology.

Philipa Varris
Head of SustainabilityMSc (Nat Resources), MAusIMM CP (Env), CDI.D.
Philipa Varris has held leadership positions in environment, health, safety and community management in the mining sector for over 25 years, primarily in Africa and Australasia and across a number of mineral commodities. Philipa has been awarded the Australian Centenary Medal for leadership in Australia’s largest community consultation and strategic vision development initiative and was recognized in 2020 as one of the WIM UK 100 Global Inspirational Women in Mining. As a champion for mining ESG leadership, Philipa has led teams recognised with the Prospectors and Developers Association of Canada Award for Environment and Social Responsibility, the AMEEF Award for Environmental Excellence, and the Mines and Money ESG Producer of the Year Award, amongst others. Philipa is a Non-Executive Director of EnviroGold Global and is a member of the UK Committee of the Australian Institute of Mining and Metallurgy (AusIMM).

Leo Neves
General CounselLL.B., LL.M. (Corporate & Securities)
Leo Neves has over 20 years of experience having developed his legal career at law firms Pinheiro Neto Advogados (Brazil), McMillan LLP (Canada) and Fasken Martineau LLP (UK). He has also acted inhouse for various mining companies, including Ferrous Resources where he spent 9 years as Head of Legal and Company Secretary until its acquisition by Vale S.A. in 2019. Prior to joining Horizonte, Mr Neves acted as a senior legal consultant for global law firm Linklaters LLP (Re:link, London). Mr Neves holds an LL.B. degree from University of Brasília (UnB) and an LL.M. degree from the London School of Economics and Political Science (LSE). He is qualified to practice as a solicitor in England and Wales, as well as in Brazil and Portugal (advogado).


Tiago Miranda
Head of Finance.
Mr. Miranda is an experienced finance professional with significant experience in the mining industry. Previously he was Financial Controller for Equniox Gold and Ferrous Resources, both located in Belo Horizonte, Brazil where we was responsible for the reporting, accounting and tax functions. Mr. Miranda has an MBA in Finance and trained at Deloitte.

Leo Vianna
Araguaia Project Director.
Mr. Vianna is a Mechanical & Mechatronic Engineer with over 24 years experience in project implementation & management. He was previously Project Director for Vale’s B$1.9B Bahodopi nickel project (REKEF processing plant) in Asia. He has significant experience in Project Management (FEL methodology and PMI), Engineering, Construction, Maintenance and Health & Safety and has worked in Brazil, Mozambique, South Africa, Guinea, United Arab Emirates. Mr. Vianna holds a bachelor's degree in mechatronics engineering from CEFET – Rio de Janeiro and an MBA in corporate finance from PUC – Rio de Janeiro.

Antonio Valério da Silva
Local Legal RepresentativeBSc.
Mr da Silva is a Brazilian geologist with over 35 years of mineral industry experience. He worked for five years in the Brazilian Mines department during which he developed a keen understanding of the Brazilian mining code and the associated legal obligations. This was followed by 11 years working for consulting companies on a variety of projects in the Amazon region of Brazil. This included a period with Docegeo, the exploration arm of Vale and Empresas Nucleares Brasileiras, the government`s nuclear mineral exploration company. Since 1983 he has acted as a consultant to a number of local mining companies and in 1986 he co-founded MVR which has worked with companies including BHP, AngloGold and most recently GoldCorp Inc. He has a geology degree from Pará State University and lives in Belém, Brazil. He is a legal representative of the Group`s Brazilian subsidiaries.