Hi Christine,

One or both of these may be your James Gardiner:
1871/4658/f126/p39, Ecclesfield. Jas Gardiner, 16, Miner, born Sheffield. He is living with a family that has been mis-transcribed on Ancestry as Custer, but their surname is actually Sylvester.
1861/3486/f122/p27, Sheffield Union Workhouse. Jas Gardiner, 5, Inmate, born Unknown.
Not much help though even if they are both right as no parents are present in either census.

Patrick