Hi Sharon- thanks for writing in. Would you know Sharon if the ring is an antique, are they antique gold hallmarks? Or are they vintage jewelry hallmarks?
Although you mention a crown and 22, they don't sound like British Hallmarks as the UK standard mark is a crown in a square box immediately followed by 22 in another square. The "MM" initials sound like the sponsor mark. You might like to try the link "Jewelry Marks 1922" in Jewelry Resources.
