Old thread, but a few points:
- Lab-created diamonds are not "fake." The other poster was not talking about moissanite, cz or other diamond substitutes. They are real diamonds, and they are typically of superior quality mined dimaonds. The only way that a jeweler can tell the difference is because they typically have a microscopic laser signature identifying them as lab-created. Otherwise, they're the same. You only save about 20% off the price of mined diamonds, so it's not an incredible deal, but at least your money isn't going into the hands of an international criminal antitrust conspiracy that's complicit in some of the worst human rights abuses in the world. Bottom line: same stones, but some are produced by entrepreneurial scientists, while others are produced by slaves.
- Diamonds, even lab-created ones, are absurdly expensive, and many women have no idea. They may say, "oh, I don't want anything too extravagant," but they don't realize that the "standard" 1.5ct diamond that they see their friends wearing may cost over 15k without the setting. When they realize that, and they realize how far that could go towards remodeling your kitchen or something, suddenly they may become a lot more interested in an affordable diamond substitute--which nobody other than a jeweler will ever recognize. If she's cool with something fake, then go for it. Just don't suggest it yourself. Let her bring it up after she gets a better sense of the economics.
- If you get a fake, you can actually be honest about it with most people, and they will not care. I can't tell you how many of my friends (who live in million+ dollar houses and condos) have been open about the fact that their rings are moissanite. It's post-2008, and financial responsibility is cool again.
- "Used" diamonds are a great deal. You need to get them appraised and re-set, but that's by far the way to go if you want the "real thing" and you don't want to pay a fortune. Pawn shops are okay. Local auction houses are often the best. The one problem is that a lot of old diamonds were not cut with the same level of sophistication as modern diamonds, so they may not have the same fire. Trust your eye, because that's what will matter in the end. If it looks gorgeous and sparkly, especially once you get it out from under the crazy lights they have pointed at it, then it's worth taking the time to get it appraised.
- Pave is very trendy at the moment, but it's a reasonably affordable way to make a smaller diamond look huge and bright, so that's something to consider.