[alwaysinshade]

> wait till she goes to work or talks to her friends who expect to see it

You can always game the system. My wife purchased a lab-made champagne diamond (colouring is from nitrogen IIRC). It was a pretty damn big rock, had only VVS inclusions and was cheap. Slap that thing in a gold band and your wife-to-be has a real diamond - your average jeweler won't have the tools to spot that it's artificial unless it's tagged. Thing was, my wife was a chem student at the time and thought it was cool. I was a young bloke with something to prove so I purchased the real-deal and spent the next three years paying it off.

Moral: marry nerds. And perhaps swallow your pride.