Can you identify hallmarks on my gold ring?

by Janice
(USA- California)

Hello,

I have an antique European, 18K Turquoise Diamond Ring and there are three hallmarks on it. Two hallmarks I can not identify. One appears to be a Maltese Cross and the other one a sailing ship. Do you know what they signify? I have attached a picture of the hallmarks on the ring.

Thanks for your help!
Janice