What is the different of “Monture” and “Dépose” means in antique jewelry?

Monture means the designer use the stones of the client, sometimes for the main stones or sometimes for stones around, then the jewelry house designs the pieces and make for their client.

Dépose means pattern is deposit - “exclusive”patented design

 The rights or patent granted for an exclusive jewelry design in France.This is a legal monopoly on the appearance, i.e. other people are not allowed to make an object with an identical appearance.  

Occasionally in the world of antiques, you may come across a mark, DEP, which could mean either Depose or Deponiert. This mark is commonly found on German or French bisque dolls, celluloid, porcelain, jewelry, glass or metal goods. Dep stands for the German word Deponiert which means registered, or copyright. Dep is also a shortened form of Depose which is French for registered. 

Without knowing a manufacturer or country of origin, it is safe to say that if your item is marked DEP, it is most likely of French or German manufacture.