Funny you should say that as I told my wife the same thing after our second time. People are always selling jewelry and diamonds are one of those things that hold their value esp. in loose stones where you could buy one at the reduced price and then get a confirmed appraisel and then sell it once back home. The real trick is to find ways to get into programs that pay you with points when you use their card...then use those points to get goods and services. When I discovered that a "card" will convert charges ( any charge ) to points it was "go time" for me as I started using my card to pay my mortgage..my gas,,my groceries and then pay the card off at the end of the month. I'd say we average about 4,000 points a month which in real terms is: 2 free days in a hotel/3 or 4 days in a hotel or if you save enough in a years time it can pay for a weeks cruise for two in the Caribbean which is what we do.
Not sure I would sell any of the jewelry we have bought for a gain...something not right about that to me.