[pearlieq]

Buy something that fits into your budget! You can always upgrade later. You're sure not going to be wanting to pay on a ring while you've got wedding expenses.

Do you have any idea what your girlfriend likes in terms of rings? Has she ever pointed out a ring or admired a friend's ring that you can remember? Are you close enough to her mother, sister, or best friend to ask them for help?

If you have no info to go on, the safest thing you can choose would be a diamond solitaire with either a round or princess cut. I wouldn't recommend buying any other cut than that unless you know for sure it's something she likes.

Take a look at the rings or jewelry she already wears. Is it silver or gold? If she wears mostly silver/white gold, buy her a white gold or platinum ring. If it's mostly gold, buy her a yellow gold ring.

Actually buying the ring revolves around finding the perfect balance between size, quality of the diamond, and price.

Things can get pretty technical when grading the quality of a diamond. The two most important factors to keep an eye on are Clarity (a measure of flaws in the diamond) and Color (how close to colorless is the diamond).

Clarity measures the flaws (little specs or bits of cloudiness) in a diamond. The flaws are called inclusions. Most diamonds for sale in commercial jewelers shops are going to be grade VS1/VS2 (very slightly imperfect) or S1/S2 (slightly imperfect). I would recommend sticking with a stone with VS2 quality or better. VS1/VS2 stones have small flaws, but they are not visible to the naked eye. The flaws in S1/S2 stones are visible to the naked eye.

Color grading measures diamonds on an alphabetical scale from D to Z in terms of how yellow they are. A "D" color diamond would be perfectly colorless and a "Z" diamond would be totally yellow. This factor isn't so important, since it's not like your girlfriend will be comparing her ring to a color chart! If the stone looks clear and bright to you, don't worry too much about the color rating.

Once you pick a stone you like, ask to see the certificate or grading report. That will list out and certify all of the measurements and quality gradings for the stone. Make sure the certificate matches what you've been told about the diamond.

The shop will likely also give you an appraisal from IGI. Ignore it. It usually has a grossly inflated price. Trust comparison shopping instead to get an idea of how much the stone "should" cost.

Good luck and congrats on your upcoming engagement!