3 Pieces, Metal, Thin, Pieced Together and Shaped like a playing card

[detectorFRED]

Size: (2.25 × 3.5 inches (57 × 89 mm)). Found in the woods outside of 15 miles outside of Philadelphia. Is it corrosion or does the center piece slightly resemble a half Moon or hatched egg? Thanks

 

[A2coins]

looks like a key hole

 

[detectorFRED]

That never crossed my mind. ��

 

[cudamark]

Part of a cabinet or drawer lock.

 

[old digger]

It's a skeleton key lock.