my thoughts on diamonds..about 18 or so years ago i spent 10G on a rock for my wife at the diamond exchange in Boston...very nice 2.5 ct emerald cut. about 10 years ago the wife and i were going thru some extremely difficult times and tried to sell her diamond. the dealer that we had bought the diamond from offered us $.10 on the dollar for the stone. never guess where i told them to go!!!
I ended up pawning my wedding ring (which also had 3- .25ct stones in it) got $400 for the gold.. bottom line for me. i will never spend that kind of money on another diamond again...it's an hierloom not an investment of any kind.
still now though the wifes ring means more to us now than it did then..good times and bad the wife, ring, and I have survived
best wishes and luck to you mikey