This is a pin, using magnets on the back as to not damage clothing, that uses a stainless steel watch case filled with two pieces from separate antique watches.  The smaller plate on the upper side of the photo, was made in 1930 and the other plate on the bottom side of the photo was made in 1905.  Both pieces were made by the Elgin National Watch Company.  In the center, is a watch balance cock and a gear.  Everything is under a coat of resin.