Was going for a cleaner, still in use look for this chest. Something a thief may be looking for while skulking about the castle.
Wood and polished inlay on top were textures I already had. Metal was a gray base, with a scratch layer overlayed. Also added a little color overlay to break up the gray. For adding some color to metal I like to use photos of motor oil which may sound strange. A photo of standing motor oil, like from a parking lot where dripping oil has sat, collected dirt, and creates those pretty streaks of color actually works pretty well. Just overlay at low opacity.
The metal pattern was created from a black/white knotwork image. That can be used to crop the metal, and then for the normal map creation. The pattern was just cut/pasted around the edges. A quick dodge to corners/edges brings out some highlights.
The rivet thingies were put on last minute and I didn't have time to get them better lined up.