This may seem like a really dumb question, but here's my situation. My GF is not into very gaudy jewelry and she has small hands, so when I propose, I'm not looking for a center diamond bigger than 1.25ct. That said, I want to get a nice stone. I have been looking at stones in the VS1-VS2 clarity, E,F & G color with excellent to ideal cut grades. The stones have ranged from about $8,500-$11,000 that I have seen. I haven't done enough research to really work out the best price just yet, because I am in no hurry to propose. But, I am completely ignorant to the diamond trade and I'm concerned about spending that type of money with so little knowledge. If somebody handed me a VS2, G, Excellent cut and told me it was VS1,E, Ideal I would have no way of knowing. If I look at the stones side by side, I see color & clarity differences, but I can't tell the cut quality difference at all. Plus, if I order a stone online, I don't have that side by side comparison option. So what is it that stops someone from giving me a stone with a GIA cert that actually belongs to a different stone? Is it just basic jeweler etiquette and integrity at stake or is there some board of oversight that penalizes dishonest dealers? I hope I don't offend anyone with that question, but it has been nagging at me so I wanted to ask some experts.