Letter and numbers stamped in my ring.

Q

Hi, I recently inherited a white gold (18k) diamond ring,
There’s a D368 stamped on it aside from the 18K 750 stamped in the ring, I just want to understand what this means because im taking it to a jewelry store to have it fixed 1 stone is missing when I received the ring so I thought I should ask around first before I go in person, at least I have a little bit of information aside from the 18k that is obvious marked in the ring. I could attached pictures but don’t know how to do that, any help/advice from you is greatly appreciated.
Thank you.

A

Hi Legarda,

750 and 18k essentially has the same meaning–75% pure gold. The D368 could be a manufacturer’s stamp. Have a great day!