The first to last step in the uranium refining process is the Yellow Cake Slurry. (AFP)
This is what we know: two foreign nationals were arrested in Durban with narcotics and 1kg of suspected uranium. No one knows where they got it and who they were planning to sell it to. Some experts think they were enticed by the "perceived" value of uranium, but there is always the possibility that it could fall into the hands of someone who would know how to turn it into a weapon.
Semirefined uranium ore, known as yellow cake, is more toxic than radio-active. However, as South Africa plans to expand its nuclear power station fleet and is investigating the possibility of enriching uranium, it cannot be seen to be the site of an illegal yellow cake trade.
A nuclear expert, who spoke on condition of anonymity, said: "The low-level smuggling of uranium takes place on a regular basis all over the world … The International Atomic Energy Agency [IAEA] tries to keep tabs on it."
Requests for comment from the IAEA were unsuccessful.
The expert intimated that, although illicit trade was "not a good thing", it was not serious because it was not possible to enrich uranium in your back yard.
Phumzile Tselane, chief executive of the South African Nuclear Energy Corporation (Necsa), said that yellow cake contained only 0.7% of the uranium variant (Ur-235) that is radioactive, and it needs to be enriched above 20% to become a radioactive threat. "Conversion … and enrichment are difficult to do without an elaborate infrastructure and highly sophisticated enrichment technology," he said.
There is a perception that, because it is used in the manufacture of nuclear weapons and illegal possession of it in South Africa carries a 10-year jail sentence, it is valuable. The spot price of yellow cake is about $70/kg, but enriched uranium is substantially more expensive.
The nuclear expert said that, "in terms of an overall national inventory", 1kg was "a small amount … [but] you need to find out where it comes from".
Although it is only one ingredient in a technically sophisticated process, it does not make the incident any less alarming. Police believe that it was destined for the black market.
Tselane said it would be difficult to sell 1kg of uranium to a bona fide nuclear player. "All the established reputable enrichment companies (and all nuclear power-plant operators, conversion facilities and fuel fabricators) are under safeguards and have to account for all nuclear materials and their transactions."
But there are countries that would like to be nuclear players, such as Iran, that do not comply with these safeguards. According to media reports, organisations such as United Against a Nuclear Iran, a US-based lobby group, believe that Iran could be using African countries as a conduit for nuclear materials.
A sample of the seized yellow cake has been sent to Necsa to determine its chemical composition and where it came from, but the question of where it was going is perhaps more important – and more difficult to answer. Are criminals starting to think that uranium can be moved in the same way as cocaine or ecstasy, or was it intended for someone who might know what to do with it?