With its more than ninety year heritage as a leading engineering-project house and equipment supplier, Zenith Engineering N.V. serves a range of industries worldwide. Our focus is on delivering innovative solutions to unlock the value of natural resources, through converting them into marketable products. Client access and project management services are provided globally through FOX’s network of permanent international offices located in Australia, China, India, Russia, North and South America, Southern Africa, the United Kingdom, and the Netherlands. Services offered include, but are not limited to, multi-disciplinary engineering, specialist niche technologies, equipment procurement, supply and related services, project finance facilitation, contracting and project execution management. Zenith is committed to Delivering Excellence in everything that it does.

Gold Ore Processing

FOX’s range of services covers all processes needed for the recovery of gold, from ore to bullion (doré) and fine gold.

  • Converting run-of-mine (ROM) ore into saleable products.
  • Integrating engineering and process know-how in development and optimisation of plant designs.
  • Delivering processing facilities to global environmental standards.

Gold Track Record

More than 60 gold processing plants and plant modifications worldwide include Central Rand Gold in South Africa, Sukari in Egypt, Chirano in Ghana, Beaconsfield, Mt Todd, Henty, Tanami and Nolans in Australasia, Carlin in the USA and Muruntau in the CIS.

Chirano gold plant, Ghana

Project Services

  • Consulting: Ore-body, production and market evaluation assesses project viability.
  • Feasibility studies: On-site and pilot-plant studies.
  • Project management: From inception through design and construction to commissioning, maximising success and profitability of the venture.
  • Comprehensive spares and after-sales back-up.
  • Process audits to Best Practice guidelines and the Cyanide Code.

Facilitation of Project Finance

FOX structures, negotiates and secures optimal and cost-effective financial packages for projects of all sizes.

Flexible Contract Structuring

  • Turnkey, reimbursable, EPCM, lump-sum, fixed fee, joint ventures or any combination to suit client needs.

Processing Technologies

For beneficiation of gold ore, Zenith liaises with suppliers to make unbiased selections of the best equipment for the job.

For stockpiling, materials handling, environmental protection and waste disposal, Zenith draws upon its comprehensive in-house and licensed range of engineered technologies or selects the most appropriate equipment from other suppliers.

Ore Handling and Preparation

Materials Handling

FOX designs and supplies complete materials handling systems.

  • Conveyor systems to move ore and tailings to, from and within the processing plant.
  • Stacking and reclaiming systems for efficient, effective and economic reclaiming of bulk materials.
  • Plants to process tailings and extract coarse material for use as backfill.


FOX selects and designs energy and cost-effective systems for mechanical liberation and exposure of gold from all types of gold ores.

  • Fine crushing only (up to four stages), usually for heap leach applications.
  • Conventional crushing and milling.
  • Autogenous and semi-autogenous milling.

Computer modelling of proposed comminution circuits maximises use of available data.


FOX designs effective pre-concentration processes that significantly reduce the size of a gold-recovery plant.

  • Flotation Conventional mechanical and column flotation cells.
  • Dense-media separation (DMS) FOX’s DMS technology is applied highly successfully to gold ores, particularly for retreating waste rock.
  • Gravity concentration Gravity-separation techniques including tables, jigs, centrifugal concentrators and sluices.

Gravity-concentration and carbon-in-leach circuit

Gold Extraction

FOX provides leaching plants for all types of gold ores.

Pretreatment of Refractory Ores

FOX has a depth of experience in refractory ore projects that is equal or superior to most of the other engineering companies.

  • Bacterial Oxidation Zenith applies all current technology, e.g. from Mintek and Bactech, as well as Gold Fields’ BIOX® process.
  • Pressure Oxidation Zenith has successfully applied pressure oxidation for gold processing.
  • Roasting (including whole ore roasting) – Traditional roasting technology where acid recovery results in a saleable product. – Arsenic-stabilising technologies to minimise environmental pollution.
  • Emerging Technologies Thiosulphate leaching, Augment, the Albion process, resin-in-pulp, Activox and others. Zenith also accesses other proprietary technology for treating refractory ores and concentrates.


  • Conventional Cyanidation Using air agitated pachucas or high-efficiency mechanically-agitated vessels.

Hot Product

Mineral Resources and Exploration in Africa

Mineral Resources and Exploration in Africa

The mineral industry has been played an important part in the development of civilizations throughout the world history, underpinning the…

Gypsum crushing plant in kenya

Gypsum crushing plant in kenya

Has the advantage of cheap matching, unobstructed discharge all line, reliable operating, convenient operation, high potency and saving energy. particularly…

Purification process of barite ore

Purification process of barite ore

Barite is an important mineral raw materials, as a mineral resource, without barite processed purification often can not get a…