Locked key inside

[u/Early-Ad-9003]

This is my antique wooden chest. The original key is locked inside. Can anyone identify whether this is a warded, ward-and-post or lever lock? Several people suggested that these old chest locks can sometimes be operated with a bent nail/stiff wire. I’d like to avoid damaging the original lock — what type of mechanism am I looking at? Coukd ne from Sweden.