Ladies: Do not allow yourselves to be naive. Have your engagment ring apparaised by a reputable dealer. You do not have to tell your husand/fiancee. Once that ring is on your finger, it is yours and your business.
G-d forbid you have to sell your ring, you must know its worth so you don’t get rooked. If you are old enough to get married you are old enough to find out the worth of your ring.
This has nothing to do with “but I love him”. This has to do with business.
You can also have it insured. How many times do we go to a simcha and take off our rings to wash for HaMoztie and almost forget it on the counter next to the sink? How many of these rings were “lost” because in truth the wife really didn’t liike the ring to begin with. But, this is only good if the ring is insured.