Daniel,
First, congratulations. I just got married a few months ago. I spent all of last Dec. and Jan. learning about and looking for rings. I was able to find out from her and her family/friends what her taste was, which helped a lot. For example, I found out that she would have been sincerely UNhappy with too big of a diamond. That was nice to know. Or that she had a strong preference for white vs. yellow gold, types of settings, etc.
If you have time for it, you can have fun with the searching process.
First, it is very necessary to educate yourself beyond simply knowing what Cut/Clarity/Carrat/Color refer to. You have to go in depth with each of them. And don't take the salesman's word for it.
When you go to the stores and ask them if it's GIA or IGI certified and they say "Oh, it was graded in house," and you ask them where their jeweler is certified from, they either come down on price or get insulted.
Ask them to explain scintillatin vs. brilliance vs. fire. Ask about symmetry and polish and table %, what are the pavilion and crown depth and angles, and how they affect the first three terms above, etc. NONE of the mall people can explain it, if they even understand what you are asking. They are just salesmen needing a job. However, many of the stand alone places have very educated people.
I knew none of this stuff before doing some reading.
The absolute best advice I can give is to go to
www.goodoldgold.com and read everything. Especially the 12 sections under "cut". The other three are important, but a small well-cut stone looks much bigger than a big poorly-cut one. A really good store will let you compare loose stones under a microscope and even go outside in natural sunlight. It's amazing how a good diamond will reflect light.
Also, a good store will let you choose a loose stone (so you can look at it better) and then put it in the setting you prefer at no extra charge.
I did a lot of research and that website kept coming up over an over. Very good information. I couldn't imagine not having used it. My wife is always having cashiers and other people asking to look at her ring, and it's not as big as most, it just reflects light very well.
I didn't get the most perfect cut diamond (couldn't afford one) but I got one that fell within the good limits, and it makes a big difference.
I knew nothing about jewlery before researching but by time I was ready to buy, I knew more than most salesmen. The good ones appreciated an educated consumer.
As far as what cut shape, that is very much up to the girls preference. There are a lot of choices.
As far as color/carat/clarity, it all depends on how far you want to go.
A true colorless diamond (G) is pricy and almost nobody can tell the difference between that and an I or J. Ask the dealer for a cubic zirconium (they are all colorless) to compare with and put it on a white background. I was told to use a white business card folded to 90-degrees and put them upside down beside each other.
Yellow gold is more forgiving for yellower diamonds than white and platinum.
Carat, well that just depends on taste and money.
Clarity. A perfect flawless diamond is very expensive, and probably unnecessary. A few slight inclusions in the right places can't be seen under anything less than 10x magnification and will bring the price down some. Too many though and it can look cloudy.
Again, I knew nothing before looking around, I'm just an engineer that likes to research and know that I got the most for my money.
Good luck, and if you have any time please read ALL of
www.goodoldgold.com , and then find out what your lady prefers. If you can do so without ruining the surprise.
Yeah, it is a big purchase. You don't want to skimp on it but more expensive isn't always better either. You just want to get the most for your money.
Many good stores will let you get a good ring and a cheap stone. Then after you surprise her with it you can go back and pick out the shape stone she wants and they will replace it and not charge for labor, if you are worried about ruining the surprise. My wife wanted the one I proposed with to be the one she wore, and she didn't want to go back later and choose one and find out how much it costed. She kinda likes having no idea how much I paid, more romantic she says. She said many times would be truly happy with a $50 ring...but I wouldn't have been. So I did some research.
I borrowed a little from my brother rather than financing it through the store. I didn't like the idea of a company still "owning" it while I proposed.
Anyway, I'll stop rambling.
Let me know if you have any questions, and keep us updated.
Congratulations,
Danny