Tips to buy engagement rings. 

Most important: get all the facts about the diamond as they are described by the seller, in writing, and on their own sales receipt. Do not  accept an accompanying document alone, to describe the diamond. If the seller lacks the skill to do this, then don't get your diamond from them because they may pass their own "mistake" on to you. 

Don't make any decisions about "what you want" in terms of size or ring design based on how they look IN the showcase; try on a variety of designs and shapes because they may look different on your hand than in the showcase!

Don't be misled into thinking a diamond must be as close to "flawless" as possible in order to "sparkle"; in a diamond already set in the ring setting, there are no visible differences between flawless, VVS 1, VVS2, VS1, VS2 and often even in SI1 or SI2! This "invisible" difference can make a huge difference in cost but in most cases they can only be seen when examined with the jeweler's 10-power magnifying lens.

In terms of color, "D" is the rarest (and also the first letter of the word "Diamond") but no one can usually see any difference between D-color vs E-color, or between E-color and F-color but the cost difference can be dramatic. Similarly for the other colors in the D-Z rating system. So don't agonize over one of two color-grades.

If "size" matters, consider oval and marquise shapes, both of which look larger for their weight than a round diamond does.

Use your own eye to decide which diamond you LIKE better, on your own hand, in terms of all of the above factors, and juggle what is most important to YOU to get what you really want. If you want a diamond of a specific size, and you have a limited budget, you will have to juggle the color and clarity to stay within your budget. However, if a diamond seems to lack the liveliness and fiery character that make diamond so special, it is probably cut poorly. Most people don't know that the most important factor affecting the way light enters the stone and gets reflected back to your eye (seen as "brilliance" and "fire") is the skill and precision of the cutting, and poorly cut diamonds sell for much less than — as much as 50% less — than well cut diamonds. 

If your budget is too small for a diamond as large as you'd hoped, consider a multi-stone ring—a center diamond surrounded by a ring of smaller diamonds is very popular and creates greater impact as a ring than a single smaller stone, and may be the perfect solution! Or, another popular style is a 3-stone ring, which can be very symbolic (the bride, the groom, eternity being one interpretation but there are others as well); the impact of 3 diamonds, either all the same size, or one slightly larger at the center, with a slightly smaller stone on each side, is very classic and elegant. 

For some, having a birthstone at the center, flanked on each side by a diamond (especially a heart-shape diamond) can be distinctive, with the added advantage of adding a personal element. Some brides opt to have the center stone be the birthstone of her fiancé, rather than her own! And some prefer to have a diamond in the center and her birthstone on one side and his on the other! There are many creative ways to incorporate this personalized element! 

Once you've selected the diamond or gemstone for your ring) and have all the facts (the 4Cs) in writing on the sales receipt, the last step is the most important: verify that all the representations are accurate and reliable. Even in cases where a GIA report accompanies the stone, the stone could have been damaged since it was issued, or it may be a counterfeit report (numerous cases have been reported in recent years). Seek someone who holds respected credentials by checking for a gemologist-appraiser by visiting any of the following sites: 

"Certified Master Gemologist" (awarded by the Accredited Gemologists Association — accreditedgemologists.org)

"Certified Gemologist-Appraiser" or "Independent Gemologist Appraiser" (Awarded by the American Gem Society — americangemsociety.org

"Master Gemologist Appraiser" (awarded by The American Society of Appraisers — https://www.appraisers.org/Disciplines/Gems-Jewelry