This is pure Belgian.

Francois Celerier of Wandre, a suburb of Liege was active from 1872 to 1877. He held 5 patents for single and double guns. MAL had 2 of his guns on display at one point.

There is some indication that he took over the business of Lambert Ghaye, also of Liege, who was active 1855 to 1872.
http://www.littlegun.be/arme%20belge/artisans%20identifies%20g/a%20ghaye%20gb.htm

Apparently neither of them ever registered a trade mark.

Pete