This unusual, and quite uncommon, window latch is cast bronze.
It mounts on the bottom of the window and locks into its keeper which is
mortised into the sill. Upon unlocking the latch, the top portion of the latch
then serves as a sash (or window) lift.
The latch back plate measures 1 7/8″ x 1 1/2 inches.
The keeper plate measures 1 3/4″ x 3/4 inch.
We have not cleaned this latch. It is in its original condition and patina.