I just found a Greener 12 bore BLNE with side safety, 30 inch Damascus barrels s/n 34824 and "list No 57" after the serial number.
According to my friend's British gunmaker's book it was made around 1890
What was "List No 57?"
A bit beat up, but barrels are in good shape, no pits, and the gun is tight on face. It will clean up nicely and I got it for a song.
Mike