St etienne shotgun

[heronfish]

Can someone help me with a st. Etienne 1874 shotgun
Was sold to me as a 20 gauge.
is there marks I should be looking for as per identifying marks?
And what is a potential value.

 

[sunray]

St. Etienne will be French. Any shotgun made in 1874 and anywhere near that date, will be Damascus and BP only. Do not even think about shooting it with modern ammo.
Markings will be on the barrel. Likely under the fore stock.
Value depends on condition primarily. There are Model 1874 rifles that were converted to shotguns too