The listing, monterey coal necklace and tie tac marked 10k has ended.
I have a 10k marked emb cto and r in circle and it says monterey coal co. also has 3 safires in it.chain marked 1/20 12k. the tie tack says 10k cto r in circle and monterey coal co. the metal pinch thing at the end says sterling. the cto stands for trademark used by oc tanner jewelry co. you can look it up on internet! My husband worked for monterey coal for 30 yrs. These were service awards!