I live in NYC, so have access to the diamond district
Don't go to the diamond district. You'll just get a lot of high-pressure sales tactics and, likely, misleading information.
I am leaning towards an artificial diamond
Cubic zirconia? The main thing to be sure of is whether your GF is fine with that. If she is, just order a huge one online, they'll be cheap.
My price range
Your price range for the complete ring or just for the stone? You can pick the stone and the design separately, that's common.
Generally speaking, you need to figure out first if you want a natural diamond or a cubic zirconia stone -- that will greatly affect your budget, the stone size (and so the ring design), etc.
Are you picking out the ring entirely on your own or you are consulting with your GF?
Cubic zirconia? The main thing to be sure of is whether your GF is fine with that. If she is, just order a huge one online, they'll be cheap.
He likely means a synthetic, i.e. lab-grown, diamond. This site has the best Google SEO.
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