Not necessarily, the later one sounds larger than the original so he may not have removed the original, and replaced it but the later one got hopelessly damaged in the fire, or removed by Marcone when converting it into a cell - iron would be dangerous to those of the Fae persuasion and provide a potential weapon to an inmate.
Two mysteries cancelling each other out Little Chicago was made of Pewter, it has a much lower melting point than Copper silver and iron. The heat in the lab was high enough to melt Little Chicago and ran all over the new circle, hopelessly fouling it leading to its removal.
Take your pick.