Fine Steel refers to steel that has had extra time spent on it. Either a few extra runs in the refining of the raw metal, perhaps a bit more time spent in the balance of the blade or the angle of the armor plates; a craftsman made this metal. This grade can be found on any Prime or Plane.
Due to the workmanship, items made of Fine Steel weight 10% less than normal and cost 10x as much. Weapons gain a +1 to hit OR damage.