I remember going to an antique mall, that was well known for high prices, and found a little gold filled telco "charm" with a similar gold attachment set with 3 stones. The price was 5 bucks each and they had 2 shoe box sized boxes of them on the floor. This was when gold was around 1800-1900 per ounce.
Turns out the little attachment was 10k and worth around 60 bucks. I went back and bought them all and thats the day i learned about gold settings attached to gold filled pieces of jewelry lol.