At my place of work I just had a piece come across my desk that I need some help identifying. This pocket watch chain has a fancy link, is made of 18K yelow gold and has a stamp I just cannot seem to be able to locate. Any help would be appreciated. On the T-Bar as well as the clasp it is stamped M&M and on the other side of the bar there is a picture of a crown in one box and an "18" in a box right next to it. The crown was incredibly hard to photograph so I apologize if the picture is of not a high enough quality.
thanks for any help