Identifying Gold & Diamond Rings: Understanding '18kt' & 'AD' Stamps

Question
I have a gold ring my aunt gave me, she says she bought it from an antique store. It's stamped 18 on one side and AD on the other. Could u please tell me what the AD means? I'd be very greatful thanks

Answer
Hi Louise,

The 18 should be followed by kt.  It is possible with an 18kt antique ring that the kt has worn away over time.  The AD could be the makers mark.  This requires some time searching on your part to find out.  I have provided links to various sites that list makers marks and hallmarks in past answers.