The trouble in the aluminium sector has claimed a major scalp.
Mining giant Rio Tinto (Xetra: 855018 - news) announced last Thursday that it would have to write down its aluminium assets by another $11bn (£7bn) or so, on top of a surprise $3bn hit on a misjudged coal deal in Mozambique. The fall-out meant chief executive, Tom Albanese, resigned with immediate effect .
The aluminium arm has long been a problem for Rio Tinto, after it bought Canadian company Alcan for $38bn in 2007, just before the market crashed.
Estimates vary, with the detail of the latest write-downs to be revealed at Rio's full-year results next month, but analysts think about $28bn has now been written off Alcan in total.
Certainly, Rio embroiled itself in an M&A disaster. But it is far from the only aluminium producer feeling the pain.
The problems in the energy intensive sector are well known, with overcapacity and rising costs meaning many operations have become uneconomical.
And the situation did not improve last year, according to Rio, as it explained the latest blot on its balance sheet.
"The further deterioration in aluminium market conditions in 2012, together with strong currencies in certain regions and high energy and raw material costs, has had a negative impact on the current market values in the aluminium industry," it said.
Don't hold your breath for an improvement any time soon. Fitch, the credit rating agency, is not optimistic. Rio's latest writedown only supports its view that "weak pricing and net market surpluses are likely to continue for at least the next two years, pressuring producer profitability".
Between 30pc and 50pc of the metal's producers are failing to break even, it estimates, as high stock levels keep official prices in check and cheap electricity becomes more scarce.
It also notes that more than 5m tonnes of aluminium is held in official London Metal Exchange warehouses and reckons that probably the same volume is held in unofficial storage. That points to a heavy surplus of the metal.
In response to the terrible conditions, producers have cut back, but not enough. People do pay high premiums in some markets to actually lay their hands on the metal, since up to 70pc of global stocks are tied up in financial transactions, Fitch notes.
However, a particular issue for producers elsewhere is that in China, political will and the high premiums paid locally for aluminium have helped many smelters stay in operation, putting pressure on rivals.
And as for the cheerier sentiment in the wider metals market?
Overall, last year was not great for commodities. Investors only saw profits in passive, long-only investments in the grains and, to a certain extent, the precious metals sectors, notes Ole Hansen, head of commodity strategy at Saxo Bank. "Investors will look towards 2013 hoping for better opportunities to emerge than during 2012," he says.
And, generally, it seems the market feels the global economic environment is improving. Last year was "sub-trend" for commodities as companies let their stocks of raw materials run down, say analysts at Macquarie, but they think 2013 will be a year of recovery albeit "subdued" for commodity markets.
"An end to the destock cycle which weighed on industrial commodities over the past six months should help bolster apparent demand," they argue.
"The fundamentals for most metals do not support sustained big increases in prices, in our view. Most base metals are in surplus this year, stocks are comfortable and the supply picture is ample, though not without risk."
They conclude, "for many metals, we would view this as an opportunity to sell short, particularly when price action starts to look a bit frothy as aluminium is already."
= Concerns raised about wheat crop =
Wheat futures rose sharply last week as it became clear the drought in the US Midwest would continue, raising concerns about this year's crop.
The drought will probably persist over the next three months because the dry earth isn't getting soaked by winter storms, the US Climate Prediction Center said on Thursday.
"On the new wheat crop, traders remain concerned about the weather as analysts believe as much as 30pc of Kansas's wheat crop was destroyed after sprouting on dry land," Arnaud Saulais, a commodity broker told Bloomberg.
Soybean prices also jumped almost 5pc over the week.
= Germany's central bank boosts confidence by bringing home gold =
Last week, Germany's central bank unveiled plans to repatriate gold held in foreign vaults.
The Bundesbank will bring home 674 tonnes of their total 3,391 metric tonne gold reserves from vaults in Paris and New York to restore public confidence in the safety of Germany's gold reserves.
"We view the repatriation and upgrade of old gold by the Western World's central banks as a further positive in gold's evolution as a legitimate form of money," Deutsche Bank (Xetra: 514000 - news) analyst Daniel Brebner said.
"While this is unlikely to have any impact on the near-term price performance of the metal, it could have important longer-term implications."
Over the past several years central banks have moved from being net sellers of gold to net buyers. Indeed, central bank buying is central to the case for gold hitting $1,900 in the first half of this year, according to precious metals advocate GFMS.
Central banks, known as the official sector, added the most gold to reserves in 48 years in 2012 and are expected to buy another 280 tonnes in the first half.
Official sector buying of gold rose 17pc in 2012 on a year-on-year basis to 536 tonnes.
China is expected to be a major buyer, increasing the proportion of its reserves held in gold. China currently holds $1.17 trillion of US Treasury bills in its reserves.