Trans Hex Group
Trans Hex Group mines diamonds from the seabed off South Africa and Namibia and from alluvial ground on land in the Western Cape and Angola. The marine side runs through Trans Hex Marine, which is the former International Mining and Dredging Holdings: Trans Hex bought 100% of IMDH in 2022 and renamed it. Three ships work for it, a mining vessel, a sampling vessel and a survey and supply vessel.
The group is private, registered in South Africa in 1963 under number 1963/007579/07, and headquartered at Montague Gardens in Cape Town. It was delisted from the JSE in 2019 and is controlled by Christo Wiese and his family. Its own releases describe more than 60 years of producing gem-quality diamonds. Since September 2024 it has sold all of its marine and land production through its own tender platform in Dubai.
News and articles
Overview
- Marine mining in South Africa sits in Sea Concessions 2C and 3C, just south of the Orange River mouth, in about 130 metres of water. The company puts output there above 200,000 carats of gem-quality diamonds a year.
- Marine mining in Namibia runs as a joint venture with the concession holder, Samicor, on ground north and south of Luderitz in 30 to 105 metres of water, above 50,000 carats a year.
- The deposits are placers: diamonds eroded from kimberlites inland, carried down the Orange River and sorted along the coast. The company estimates about 3 billion carats were deposited into the ocean as the top 1,000 metres of Kaapvaal craton kimberlites eroded away.
- On the licences Trans Hex Marine works now, it puts the probable reserve base at a life of mine beyond 6 years, with the inferred resource likely to add at least 4 more as infill sampling continues.
- On land, the De Punt mine on the Western Cape coast works storm-beach gravels near bedrock, using contracted sea vessels, shallow-water shore units and beach-mining units crewed largely from Lamberts Bay and Doring Bay.
- In Angola, Trans Hex operates the Somiluana alluvial mine in Lunda Norte, about 1,000 km northeast of Luanda, and holds 33%. The mining licence was awarded in 2010.
- The company reports no seabed minerals other than diamonds. There is no nodule, crust or sulphide exposure here.
Marine operations
| Where | Ground | Water depth | Reported output | Structure |
|---|---|---|---|---|
| South Africa | Sea Concessions 2C and 3C, south of the Orange River mouth | About 130 m | More than 200,000 carats a year | Trans Hex Marine |
| Namibia | Concessions north and south of Luderitz | 30 to 105 m | More than 50,000 carats a year | Joint venture with the concession owner, Samicor, through Namibia Underwater Technologies and Mining and Nutam Operations |
The sampling ship works full time to extend the life of mine rather than to produce, which is the pattern across marine diamond mining: the resource is proved a block at a time, immediately ahead of the miner.
The fleet
| Vessel | Role | Built | Size | How it works |
|---|---|---|---|---|
| MV Ya Toivo | Mining | 1984, converted to a diamond mining vessel in 2000 | 149 m by 24 m | A 280-tonne tracked ROV is lowered on a 450-tonne winch to mine to 150 metres. It can cover more than 1,000 m² an hour and pump up to 1,600 tonnes of diamond-bearing sand and gravel an hour to the ship, and stays submerged for 7 to 10 days at a time. About 90 crew, resupplied at sea, with stays offshore exceeding 11 months. |
| MV Explorer | Sampling | 1979, converted to a sampling vessel in 2009 | 115 m by 20 m | A four-legged tool goes down through a 10 by 12 metre moon pool and drills 2.5 metre holes to 8 metres, extendable to 12. Gravel comes up by airlift, is processed on board and the residue returns to the seabed. Between 25 and 55 holes in 24 hours, depending on sediment and weather. |
| MV Good Wind | Survey and supply | 2012, acquired in 2022 | 52 m by 15 m | Hull-mounted Simrad EM 2040 multibeam and Topas 40 sub-bottom profiler with a dedicated survey control room, plus a towed SeaSPY2 magnetometer used to map magnetite-bearing palaeo-beaches. Also carries fuel, stores and spares to the other two ships so they do not have to come in. |
Trans Hex says the Explorer sampled diamond-bearing gravel in 185 metres of water off Namibia, and that this is the deepest anyone has sampled or mined for offshore diamonds. That is the company’s own claim, and no independent confirmation of it has been published.
Selling the production
Trans Hex sold historically into the open markets in South Africa and Belgium, to the State Diamond Trader in South Africa and to Sodiam, the Angolan state marketing company. It then moved to tender: the group and Trans Hex Marine appointed Kruger Diamond Traders to market and export their rough through an online tender platform, and set up Trans Hex Diamond DMCC in Dubai.
- November 2023: the group integrated ItraceIT, a Belgian traceability system combining image recognition, connected devices and blockchain records, so a parcel carries its chain of custody from the mine forward.
- September 2024: Trans Hex Auction & Tenders (TAT DMCC) opened its own secure online tender platform in Dubai, and the group said it would sell all of its marine and land production there, mine to market. The first tender ran from September 10 to 16, 2024.
- TAT also sources goods from other mines, so a tender is not necessarily all Trans Hex production.
The De Punt court case
In December 2022 Protect the West Coast and others asked the High Court to stop mining at De Punt and to set aside the mining rights, arguing that the environmental management programme was out of date and that Trans Hex was working above the high-water mark at Doringbaai. The case settled, and the settlement was made an order of court.
- Trans Hex says the mining continued and the rights remain in good standing, and that the work above the high-water mark was the filling in of old excavations left by a previous right holder, done alongside preparation of a site for a municipal abalone factory.
- Its defence rested on the applicants not having exhausted the internal appeal under section 96 of the Mineral and Petroleum Resources Development Act before going to court.
- The order formalised an undertaking the company says it has honoured since 2005, not to mine about 14 kilometres of coastline set aside as conservation areas.
- The account above is the company’s own, from its media statement of September 2023. The applicants have not been asked for their version here.
Appeals against the new West Coast authorizations
- The Department of Mineral and Petroleum Resources approved the upgraded environmental management program required by the 2023 order in March 2026. It covers Sea Concessions 11A, 12A and 13A and their surf zones, north of Doringbaai and near the Olifants River estuary.
- Protect the West Coast appealed that approval in May 2026. It argues the program rests on data collected between 2002 and 2004 and drops rehabilitation obligations set in the 2002 program.
- Trans Hex Operations has been granted environmental authorizations for marine diamond mining in Sea Concessions 11B and 13B, off Doringbaai, Strandfontein and Papendorp. Protect the West Coast has appealed both.
- On October 1, 2026, Protect the West Coast and 10 co-appellants said they had appealed an environmental authorization for Trans Hex to prospect >32,000 hectares of seabed across six West Coast concessions. They say the appeal suspends the authorization until the Department of Forestry, Fisheries and the Environment decides it.
- These accounts are Protect the West Coast’s own. Trans Hex has published no statement on the appeals.
What to watch
- Whether the Dubai tender platform holds all of the group’s production, and what that does to disclosed volumes.
- Infill sampling by the Explorer, which is what would extend the stated life of mine beyond the current 6 years plus 4.
- The Namibian joint venture with Samicor, the smaller of the two marine operations and the one with the shallower ground.
- The outcome of the appeals against the upgraded environmental management program, the mining authorizations in Sea Concessions 11B and 13B and the six-concession prospecting authorization.