For a glimpse of how quickly and unevenly economies are recovering from the pandemic, look no further than the market for shipping raw materials.

The cost of moving commodities like coal and iron ore across the world’s oceans is surging as China lifts cargo purchases. Whether the rally will withstand the economic aftershocks of the coronavirus is a thornier question.

Raw materials are reeling after President Donald Trump threatened new tariffs on Chinese goods, dashing hopes that the two sides might soon negotiate an end to the trade war that’s sapping global growth and demand for commodities.

Commodities had their best quarter in almost three years, driven by supply concerns and optimism over demand. Investors, though, might not want to get too cocky.

Commodity companies are beginning to feel the impact of President Donald Trump’s trade policies, and their earnings report cards will signal how well they’ve been able to protect shareholder value.

Commodities just posted the longest losing streak in more than three years, and analysts and investors are giving conflicting signals over whether the worst is over.