High Quality Content by WIKIPEDIA articles! McLouth Steel is a former integrated steel company. The company had three locations. The first plant was in Detroit, Michigan, the second (and significantly larger) in Trenton, Michigan and the third, a cold mill, in Gibraltar, Michigan. The Detroit plant is currently owned by Jones & Laughlin Steel Company. Around half of the Trenton plant remains, including the rolling mill, Detroit Steel Company currently owns the property. The Gibraltar cold mill is owned by Steel Rolling Holdings, and has been restarted.