Maker / backmark - Firmin. Date range - late 1800's. Here is a very nice original uniform button. Listed in good faith and to the best of my knowledge and abilities.
Irish Army Button Royal Dublin Fusiliers Late 1800's QVC Firmin 19 mm
Irish Army Button Royal Dublin Fusiliers Late 1800's QVC Hobson 19 mm
Irish Army Button 4th Royal Irish Dragoon Guards Late 1800's 1900's Dowler
Army button The East Surrey Regiment Officer QVC late 1800's Stilwell
Army button The Kings Own Borderers Officer QVC late 1800's Jennens
Army button The East Surrey Regiment Officer QVC late 1800's Jennens