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How to Buy Diamonds

How to buy diamonds

A diamond ring, tennis bracelet, necklace or pair of earrings can be the most expensive jewelry purchase you ever make. A diamond engagement ring, for example, should cost at least the equivalent of two month's salary for many people, and oftentimes much more. Not to mention that diamond jewelry can carry enormous emotional baggage; a pair of engagement rings will hopefully last a lifetime, and ideally you should never need to buy another. Learn how to buy diamond jewelry by following just a few simple tips to ensure you get the best diamond deal for your money.

What to look for in a diamond

The first thing to consider when buying a diamond is the "four C's": cut, color, clarity and carat. Cut refers to how a diamond is faceted and polished and is the most important factor to consider because it determines the level of sparkle. A highly graded stone, if not cut well, will not sparkle to its fullest potential.  Color, or more precisely colorlessness, is the second most important factor; the less color and the whiter the gem, the more valuable it is. Completely colorless diamonds are graded "D" and are extremely rare. Grades E through J will have increasing levels of tint, while anything below grade J will have significant yellow or brown shades and is best avoided.  The clarity grade describes how many natural imperfections, called "inclusions", are in the gem. The fewer there are, the more valuable the gem. Finally, carat refers to the diamond's weight and is not to be confused with "karat", which is the measure of purity for gold jewelry. One carat is 200 milligrams. It's important to remember that carat alone may not reflect the visible size of the gem; a poorly cut diamond will be too tall, hiding most of its mass within the mounting of the jewelry. A well-cut diamond, on the other hand, will be cut wider to show off more top surface area.

How to buy a diamond online

Buying diamonds sight unseen from an online seller is nerve-wracking, but it can be done safely by keeping a few guidelines in mind. First of all, choose a seller with an established reputation and good customer feedback. This holds true whether you are buying from a large retailer or online auction listing. Next, check who did the grading on the stone. There are many organizations which grade gems but the Gemological Institute of America (GIA) and American Gemological Laboratory (AGL) are the most famous and have commonly accepted grading standards and stones graded by them will have great market value. Don't hesitate to ask the seller for high-definition pictures of the jewelry from multiple angles; if you're paying top dollar for the diamond, it's worth his time and trouble to take a few more photos.

Diamond versus cubic zirconia

Some unscrupulous sellers try to pass off cubic zirconia (CZ) and moissanite as real diamonds, while others openly market them as inexpensive alternatives. To avoid being taken in by the former, the first thing to examine is the color. CZ and moissanite jewelry is much whiter and more colorless than diamond jewelry at any given price point. So if a diamond is perfectly colorless but is selling for a low price, chances are it's an imitation. Another method of uncovering a fake diamond is to gently blow your warm breath over the gem. Diamonds will unfog more quickly due to their higher thermal conductivity. If, on the other hand, the seller is openly selling CZ and moissanite jewelry as imitations, then there's no problem with it as long as you find the cost-to-quality tradeoff acceptable. Imitations are not as hard as real diamonds, so they will accumulate scratches more easily and dull over time if you don't take care of them. You have to decide for yourself if the extra cost of a real diamond is worth it.


When you're shopping for a diamond ring or other piece of jewelry, chances are it's the purchase of a lifetime. Make sure you're getting a great deal on this lifetime investment by shopping with reputable online jewelry stores like