The price of iron ore delivered to Chinese ports is 25% or more down since September and still under pressure, which is a signal that the world's economy may be heading for a severe recession.
The iron ore bubble has burst. And so too have those of copper and metallurgical coal. For some years China has been the largest importer, taking as much as half of the world's iron ore exports. Those shipments have been the main driver of prices for almost a decade.
According to commodities consultancy IndexMundi, in October 2001 Chinese buyers were paying just shy of $13 a ton for 62% iron ore fines delivered to Tianjin port. In August and September this year the average price was more than $177 a ton - almost 14 times higher in a decade. That was a far better relative performance than, to cite two examples, "safe-haven" gold or Brent crude oil.
But, as global economic fears mounted, by October this year the average was down to little more than $150 a ton. Latest quotes are in the region of $134 a ton delivered to the Chinese port, where stockpiles are mounting because steelmakers are deferring deliveries.
To make matters worse, according to talk in Hong Kong, some Chinese buyers are now arbitrarily responding to the commodity's price collapse by reneging on purchase contracts signed only a month or two back at higher prices.
Just two years ago the export market was less volatile. Back then, the major iron ore producers - Rio Tinto, Vale and BHPBilliton - would agree prices annually with their customers. But that changed, in part under pressure from the Chinese steelmakers, and prices are now set quarterly at most.
Spot prices now respond far more quickly and dramatically to changing economic conditions. Rio has gone further, with CEO Tom Albanese saying that falling prices will help accelerate the shift to shorter-term pricing. Some sales prices are already being set on a monthly basis.
Some miners are putting a brave face on things. This past week Fortescue Metals, Australia's third-largest iron ore producer, admitted that though it had recently seen prices as low as $115 a ton, they were now back up to $131 a ton. Fortescue added that it was confident Chinese demand would grow and that prices would improve. Maybe, maybe not.
Fortescue's prognosis came after its founder, Andrew Forrest, had been reported as saying that a "sensible" longer-term level would be $80 to $100 a ton. Vale has been reporting recent levels of $120 a ton. And Australia's Atlas Iron, which is among the many miners busily expanding, has been predicting a range of $120 to $140 a ton for the next three years.
The three majors are pushing ahead with expansion projects in response to rising prices. So, too, is Kumba in South Africa. No one is talking of production cuts - quite the opposite. Ukraine's Ferrexpo noted that with production cash costs of something over $50 a ton it can maintain profitable production should prices fall even further.
And, over the past three or four years, strong prices have contributed to a great deal more new production across the globe. Sierra Leone, to give a minor example, has just re-entered the export market after an absence of 30 years.
The fact remains that demand for steel remains affected by febrile demand for consumer products such as motor vehicles. That is in developed economies as well as in the booming Chinese market where consumers are feeling the pinch of tighter credit and Beijing's inflation-fighting interest rate increases.
It remains an open question as to whether the Chinese economy is in for the "hard landing" being predicted by, amongst others, influential economist Nouriel Roubini or "Doctor Doom", as he has been called.
Elsewhere, if the eurozone countries tumble into real recession by failing to deal with the problems of debt-crippled Greece and Italy, can the rest of the world be far behind? The straws are already in the wind.
