After losing three fourths of its value in five years, iron ore can get excited easily. All the more reason for investors to be skeptical of a rally in a commodity that looks trapped in China’s slowdown. As WSJ's Abheek Bhattacharya reports:

Benchmark iron-ore prices have rebounded 31% since mid-January when fears of a Chinese hard landing had commodities prices crashing across the board, according to data from the Steel Index. Shares prices of miners such as Australia-listed Fortescue Metals have followed suit. Partly, steel mills and ports in China, the center of global demand, are stocking up on iron ore. But that...