H. Plateaux
 

I'm trying to get any information on this 12 gauge sxs Damascus barrel shotgun manufactured by H. Plateaux in Belgium.

I've not heard of that maker. Probably a small shop or firm. There were hundreds of them in that part of Europe. It is a Francotte sourced A&D boxlock action however. I like the gold crown on the guard. Is the stock oval engraved?

H. Plateaux
 

There is a round shield with no engraving inlaid into the checkered butt plate.

Ok. Probably no ruling class connection then. A nice gun nonetheless.

that name is not on the list of know Belgium makers on the Belgium gun site

http://www.littlegun.be/arme%20belge...ies%20gb.htm#P

It was common for retailers, shops, and the occasional outfitter, to have their name on a gun, made by others. Otto Geiger was a well know retailer, and many of their guns were Merkels.