Day rates for Capesize ships on the spot market fell to $12,000, very close to the so-called "opex" level, the point at which a ship falls below breakeven. Since then, they've risen above $30,000 a day, according to the Baltic Exchange, a London ship broker, as booking activity has improved. Further, analysts say, iron ore inventories in China appear to have fallen.

Earlier this year, the big three iron ore miners and the steel industries of Asia and Europe (the two biggest markets for the high-quality iron ore mined in Australia and Brazil and shipped across oceans) agreed to move to a quarterly pricing contract from an annual one.

The new pricing regime has led to some interesting consequences. Steelmakers, for example, unhappy by the shift to shorter-term pricing though powerless to squelch it, quickly learned how to turn things at least a bit to their advantage.

For the miners, the average selling price of iron ore on the spot market during each quarter is used to help set the contract price for the next quarter. (Rio Tinto and Vale use a three-month average, BHP a one- and two-month average.)

Cleverly, some Chinese steelmakers seem to have decided to pull out of the market for nearly a month toward the end of the third period. Demand slackened and, sure enough, iron ore prices came down. This is seen as one of the reasons that dry-bulk rates cratered as well, of course. Now, for the fourth quarter, China's steelmakers will have wrested a lesser iron-ore contract price from its iron ore suppliers.

Volatility, therefore, appears to be the new world order. And, long term, many shipping pros continue to worry about oversupply: the impact of so many new ships scheduled for delivery from shipyards to shipowners in the next year.

>>Dry Bulk Shipping Execs Air Bullish Views

Dry bulk stocks tend to move as a block, though there are differences.

DryShips ( DRYS), for example, has been bogged down by its foray into the deepwater oil-exploration equipment industry. Eagle Bulk Shipping ( EGLE), for another example, runs a fleet of Supramax-size ships, which specialize in coal and grain hauling, not iron ore. Iron ore is mostly shipped on the enormous Capesize vessels. Thus, Eagle may not participate quite like other bulkers in a rise in day rates for Capesize ships.

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