Iron ore—the raw material that goes into making steel—is experiencing its worst week in several months. The price drop is happening because steel mills, the factories that turn ore into steel, are making less money on each batch they produce. When profits shrink, mills slow down their work or produce less, which reduces demand for iron ore.
The timing makes things worse. This time of year is typically slow for steel production anyway, so mills aren't running at full capacity. Combined with tighter margins—the gap between what mills pay for raw materials and what they earn from selling finished steel—the weak demand is pushing iron ore prices down even further.