As canaries in coal mines go, mining shares tend to be reliable harbingers of a sell-off in industrial commodities in a downturn. But although London-listed mining stocks sold off heavily in July and August, falling by almost 25 per cent, commodity prices have not uniformly followed them lower. The Dow Jones-UBS industrial metals index is at a 12-month low, and copper is at its lowest in 10 months on fears of a eurozone and US slowdown. But iron ore and coal prices remain firm. It is not yet time to call the end of the cycle.
在煤礦裏用金絲雀來預警的時代已經過去，礦業股正成爲經濟下滑時工業用大宗商品是否會遭拋售的可靠預兆。不過，雖然倫敦股市的礦業股今年7月和8月遭到猛烈拋售，價格下挫將近25%，但工業用大宗商品的價格卻並未齊刷刷地應聲下跌。由於市場擔憂歐元區和美國經濟放緩，道瓊斯-瑞銀工業金屬指數指數(Dow Jones-UBS industrial metals index)目前處在12個月以來的低位，銅價也處在10個月以來的低位。但鐵礦石和煤炭價格仍保持穩定。現在還不能認爲大宗商品週期已到終點。