Here's an interesting update I found on line at a web site for Belgium made guns. It may be the crowned crossed keys are really not anything!
A copy of the American COLT NAVY 1851 revolver called in LIEGE the “BROOKLYN BRIDGE” because of coarse engraving being reproduced on the barrel (suspension bridge and evolution of boats).
Inspired freely of the Navy Colt, it borrows the majority of its characteristics to him.
230 mm length, it is shorter than its model.
The octagonal barrel measures 100mm.
This type of weapon was manufactured by several arms manufacturers of Liège of which CLEMENT and RONGÉ and probably MASEREEL.
The majority of the marks were however whimsical such as for example the cross and crowned keys which are also reproduced on the CLEMENT-RONGÉ!
Most of these weapons were manufactured by Clément Rongé then have been resold by MASEREEL.
The lawful punches of the proofhouse of Liege are reproduced on the cylinder, namely:
Spangled ELG in a crowned oval: acceptance post 1893.
This date can appear late for a weapon with percussion but these BROOKLYN BRIDGE still appeared in the catalogue ALFA of 1911!
J spangled: countermark of the controller post 1893.
Other markings are:
PATENT SYSTEM: whimsical marking not meaning anything
Crowned cross keys: to see above.
A crowned: mark unknown and probably whimsical. One can consider A of Antoine MASEREEL but they are extremely doubtful!