When the price of a commodity such as a metal or oil skyrockets, there is usually an obvious reason.
But a rise in the price of uranium, used to produce nuclear energy, has left many in the city scratching their heads for no apparent reason.
Uranium is trading at a 15-year high above $80 a pound.
Experts say the astonishing $48 per pound increase at the start of the year is partly a sign of the times.
After years of rhetoric about reducing CO2 emissions, many countries are now formulating longer-term ambitions to use nuclear energy.
For some, such as Britain, China and Sweden, this means building a plethora of new power stations, while for others it is about extending the life of existing sites.
Keith Watson, portfolio manager of the uranium-focused Geiger Counter Fund, said: 'The big change has happened at both public and government levels, where we now have much more pro-nuclear policies.'
But this comes after the sector fell out of fashion for several years following the 2011 Fukushima power plant disaster in Japan.
Watson said: 'After Fukushima it was easy to park it in the shadows and ignore it, but as a result we have seen a lot of underinvestment.'
The world currently produces about as much uranium as is needed for use. Ramping up this production by getting new mines and processing plants operational will take time.
Uranium sales are also a so-called very tight market, where not much of the material is available to trade.
Robert Crayfourd, co-fund manager at the Geiger Counter Fund, said the disruption caused by the coup in Niger earlier this year further reduced supply.
Niger produces only 4 percent of the world's uranium – the main producers are Kazakhstan, Namibia, Canada and Australia – but it was a major supplier to France, a major producer of nuclear energy.
In the wake of this, Western utilities are even more eager to secure contracts to ensure they have long-term access to uranium. This means that there is even less to trade on the general, non-contracted market, also known as the 'spot market'. It is this spot price that has risen explosively.
Britain will be drawn into the wider battle to secure access to uranium as the government believes nuclear energy will be crucial in the coming decades.
Ministers are struggling to find funding for new projects, such as the Sizewell C power station on the Suffolk coast, and attempts are underway to set up a fleet of mini nuclear power stations, known as small modular reactors.
So is the rally likely to last? John Meyer, mining analyst at consultancy SP Angel, believes so.
Meyer said: “We see prices potentially rising annually for the next ten to twenty years, or until the world finds another source for large-scale, uninterrupted baseload energy with a low carbon footprint.”