Steenkampskraal Holdings has once again confirmed the presence of extremely high grades of thorium and rare earth elements at its project close to Vredendal on the west coast of South Africa. According to Trevor Blench, chairperson at Steenkampskraal, the thorium (Th) and rare earth elements (REEs) are the highest grades in the world. “At an average of 2.14% Th and 14.4% REE, with REEs in some areas as high as 45% TREO + Y2O3 [total rare earth oxide + yttrium oxide], this is an impressive deposit,” says Blench.
Blench says the Steenkampskraal project has many favourable attributes, including its mining-friendly jurisdiction, well-established local infrastructure with established access to the underground mine, high-grade REE orebody, continued exploration potential, and low capital requirements. The project was successfully exploited for thorium in an underground operation by Anglo American between 1952 and 1963.
The Steenkampskraal mine holds the full spectrum of rare earths, including high-value neodymium used in the manufacture of magnets, computers, and hard drives. Typically, a 3MW wind turbine uses about 500kg of neodymium and 100kg of praseodymium in the magnets for its motors. Lanthanum is used in NimH hybrid batteries with cerium and there is potential demand for over 100 million kilograms of rare earth metals for hybrid and fully electric vehicles over the next few years. A typical hybrid car uses 10kg of rare earth metals. Hybrid electric motors use dysprosium and terbium, and their component sensors use yttrium.
Total rare earth oxide deposits found around the world have an average in situ grade of between 1% and 3%. When deposits are mined, the grade is even less because the in situ mineralised material is mixed with material (waste rock) that has little or no value (the mining cut). Hard rock deposits, such as the monazite deposit at Steenkampskraal, generally have higher grades compared to beach sand deposits.
Rare earths in India are generally contained in sand deposits, while in China they are found mainly in dolomite marble, which is also associated with iron ore. When rare earths are contained in sand deposits, the extraction process is more difficult and costly when compared to rare earths deposits that are associated with monazite mineralisation.
In most other deposits in the world, the monazite mineralisation is disseminated within the deposit (in other words, the grade is diluted), whereas at Steenkampskraal the monazite (REE) mineralisation is concentrated in a reef zone from 0.02m to over 10m thick, with an average thickness of about a metre, making it easier to separate and extract the monazite.
Grades are dependent, among other factors, on the minerals in which the rare earths are contained and how the minerals are distributed within the host rock. Because of Steenkampskraal’s high grade, it is unnecessary to extract huge amounts of monazite-containing material and, therefore, large crushing vessels are not required.
Another feature of the Steenkampskraal deposit is the size of the monazite grain carrying the rare earths. The grain is larger than normal, at about 250–300 microns in diameter. This means that the monazite requires less milling, further reducing costs. Most competitors need to mill their monazite down to 50 microns. This increases costs and requires large amounts of energy. Copper, for example, needs to be milled to 75 microns.
In addition, at Steenkampskraal, 59% of the mass of the monazite is total rare earth oxides. As a result, when milling, less dust is created because of the high density, further reducing costs and lessening any negative environmental impact. The chemical treatment process is also less complex, resulting in reduced capital and operational expenditure.
In terms of the mine’s thorium deposits, the latest mineral resource estimate indicates the presence of 11 700 tons of thorium in the Steenkampskraal deposit. In October 2014, the Colorado School of Mines published a report entitled Thorium: does crustal abundance lead to economic availability. The report considers the possibility that thorium could be used as a nuclear fuel and that the demand for thorium could eventually rise to nearly 4 000 tons per year.
The report includes studies of where this thorium would be sourced and states that the Steenkampskraal mine in South Africa will be the lowest-cost producer of thorium in the world, with an estimated production cost of USD3.56 per kilogram. The second cheapest producer has an estimated production cost of USD7.98 per kilogram, and the third cheapest with a production cost of USD8.01 per kilogram.
The report indicates that the three lowest-cost producers could together produce about 3 718 tons of thorium per year, which is about the quantity that the report indicates could be required by the nuclear industry in the future. “Steenkampskraal expects to play an important role in the development and introduction of thorium as a nuclear fuel,” says Blench.
Blench adds that Steenkampskraal is designing a small, modular, low-cost, helium-cooled thorium pebble-bed modular reactor, known as the HTMR100. “It will use the thorium mined at Steenkampskraal and Steenkampskraal’s locally designed thorium/uranium pebble fuel. This is ideal for areas, such as parts of Africa, that are experiencing acute power shortages with underdeveloped or non-existing power infrastructure,” says Blench.
Steenkampskraal is designing the factory to produce the pebble fuel for the HTMR100. The fuel presents no risk of meltdown, such as that experienced at Fukushima.
Blench says that Steenkampskraal’s vision is to be the building block and provider of the foundation of a rare earths supply chain, independent of China. This strategy covers four key areas: mining thorium and rare earths at Steenkampskraal; designing a safe thorium-based nuclear reactor; designing the thorium/uranium pebble fuel for this new HTMR100 reactor; and testing and supplying safe thorium/uranium and thorium/plutonium pellet fuel for existing light water reactors(LWRs), of which there are about 350 operational worldwide.
By Trevor Blench, Chairman of Steenkampskraal Holdings, which owns the Steenkampskraal rare earths mine in the Western Cape, South Africa
Manufacturers of products ranging from batteries to electronic devices, and wind turbines to hybrid cars, are scouring the world to secure critical supplies of rare earths such as neodymium, praseodymium and dysprosium.
The increasing applications of rare earths in key industries, which include smartphones, are fuelling worldwide demand and raising the prices of some rare earths.
The Steenkampskraal mine in the Western Cape province of South Africa has the highest grades of rare earth elements in the world and with this South Africa hopes to become a significant supplier of rare earths in world markets.
The mine plans to establish a supply chain of its highly-sought-after rare earths to manufacturers around the world. Some manufacturers see the supply so critical that they have indicated interest in buying a share of the mine to secure supplies.
The rare earths known as neodymium, praseodymium and dysprosium make up about 85% of the economic value at the Steenkampskraal mine. These are key rare earth elements used in the manufacture of permanent magnets that go into most electric motors in the world.
More than half the economic value of the Steenkampskraal mine ore is in neodymium, followed by around 20% in praseodymium and 10% in dysprosium. In 2015, China produced about 80% of the global rare earths output.
Neodymium and praseodymium form the basis of neodymium-iron-boron (NdFeB) magnets. The addition of dysprosium enables these magnets to operate at high temperatures. These magnets are used in numerous products ranging from miniature speakers in smart phones to wind turbines.
NdFeB enables smaller, lighter and more powerful magnets to be manufactured for defense weapon systems. Neodymium magnets are also key components in electric cars and make appliances like air conditioners far more energy efficient. LED lighting relies on yttrium, cerium and other rare earths.
Most people have no idea about the components in smartphones. Yttrium and praseodymium are what make smartphones so small, powerful and bright. In the defence industry, rare earths are vital in laser, radar, sonar, night-vision systems, missile guidance, smart bombs, jet engines, and even the alloys on armoured vehicles.
Some manufacturers, as well as some countries, are indicating concern over China’s dominance of these strategic resources. The concentration of rare earths production in China raises the question of supply vulnerability.
Because rare earths are used for so many commercial applications, the US, Japan, Europe and other countries could be vulnerable to supply disruptions. Rare earths are considered essential to a country’s national security and economic well-being.
The Steenkampskraal mine has great value and economic potential. The mine’s rare earths basket, based on present prices, is about US$15.84 per kilo of separated rare earth oxides. The cost of the mine’s production is estimated at US$9.64 per kilo of separated rare earths. Gross profit is estimated at US$6.20 per kilo.
With these prices and volumes, the company would have a total sales value of about US$43 million per year, a total cost of about US$26 million per year and a gross profit around US$17 million per year.
Steenkampskraal presently has a Mineral Resource Estimate of 605,000 tons of ore with an average grade of 14.4% Total Rare Earth Oxides (TREO) for a total of 86,900 tons of contained TREO.
• Has a jurisdictional mine site area of 474 hectares.
• Surrounding farm areas of 6 990 hectares have been purchased as buffer
zones for the mine operations.
• STL is part of the International Thorium Consortium
• Aim is to commercialize thorium as a supplement fuel in conventional nuclear reactors
• Irradiation testing of thorium-oxide LWR pellets in the Halden Reactor (Norway) started on 25 April 2013
• Second round of test irradiation is underway.
• Two rigs in the reactor containing various Thorium fuel compositions
Steenkampskraal Thorium Ltd. (STL) is a South African registered company, supported by private share holders and is based in Centurion
• STL is developing thorium containing fuel as an environmentally cleaner, safe and efficient energy source from the point at which the thorium is mined to the acquisition of fuel
• STL is designing a small modular High Temperature Reactor and a strategy for Fuel ProductionThorium is a naturally occurring radioactive element found in the earths crust
• Thorium is often produced as part of the tailings in Rare Earth Element separation processes
• It is approximately 4-5 times more abundant than uranium
• Thorium is not fissile but fertile; this means that thorium can
capture a neutron to produce fissile 233U • The fission of Thorium does not generate minor actinides
• Thorium containing fuel can facilitate the reduction of world-wide plutonium stockpiles
• STL has built up a technical team of specialists to design and build High Temperature Reactors (HTR) and a fuel plant
• Five years of engineering is completed on a 30MWth and a 100MWth HTR
• STL calls its HTR a High Temperature Modular Reactor (HTMR)
• Marketing has been initiated in various countries
• The objective is cleaner, safer, sustainable and affordable nuclear power and process heat for desalination
The HTMR100 and HTMR30 are Gen IV 100MWt and 30MWt helium cooled reactors that feature a uranium, uranium-thorium or plutonium-thorium fuel cycles
• Ceramic spherical fuel elements are used in an OTTO cycle and allows on-line fuelling. Used fuel only requires simple dry cooling
• This fuel technology has excellent demonstrated safety characteristics
• The HTMR can be utilised for power generation and process heat applications, specifically desalination
• Small size and modular construction result in shorter building times and lower costs and allows for future modular expansion. The Reactor Vessel is designed to be road transportable