Diamond Buying Guide and the 4 C's

A lot of people see diamonds as white, sparkly rocks. While that is partly true (diamonds are actually minerals, not rocks!) there is still so much more that goes into what makes a diamond beautiful and sparkly. The biggest of these, is the 4 C’s: Carat, Color, Clarity and Cut. Each one of these factors contributes to the price and with the right combination, you can usually find the perfect diamond within your budget.  I’m going to break down each one of these for you and hopefully get you to a place where you may feel a bit more comfortable around these white sparkly stones. 

Carat: Let’s start with the easy one. Carat refers to the weight. Diamonds are almost always referred to by their weight- not usually their size. A 1 carat diamond is the most familiar, but you can buy a diamond at any size and the price will adjust accordingly. A common starter point for an engagement ring is anywhere between .75ct and 1.00 carat. There are a few weights that usually make the price jump and those are always at the quarter mark (.25, .50, .75, 1.00, 1.25, etc). If you stay just before that quarter mark, you can land in the “sweet spot” and get a lower price for a similar size appearance. So for example, if you want the look of a .75ct in size, you could go with a .70ct or a .72ct and get a slightly better price while still appearing almost the same size as the .75ct. Incidentally, this isn’t a trade secret so the options of diamonds in the “sweet spots” are slim- especially in the .92-.99ct range.

Color: The color of a diamond is graded on a scale of D through Z. As you get lower on the color scale, diamonds will start to gain a yellow or brownish tint. The color scale is bracketed which makes it a little bit easier to follow. D, E and F are considered colorless. That means that to the untrained eye, you can see no color. G, H, I and J are considered near colorless. That means that you may be able to see slight color, especially in I and J. K, L and M are considered faint, which means you may notice a yellow tint. After M, the color grades are grouped (N-O, P-Q) and they show obvious color.

Image source: www.gia.edu

Image source: www.gia.edu

There are sweet spots in color too! If you want a colorless diamond, but don’t want to pay for a D, E or F, go for a G. G is so close and definitely appears quite white, especially when set in a ring. H and I are great too, especially if color isn’t something that jumps out at you or is one of your priorities. Here’s a tip: If you are getting a yellow gold or rose gold ring, you can get away with a lower color diamond and on the contrary- if you get a white gold setting, the color of an H or I may stand out more than it would in a warmer hued ring.

Clarity: Clarity measures the inclusions inside the diamond. Almost all of the clarity grades cannot be seen to the unaided eye but I1, I2 and sometimes SI2 are visible without magnification. Stones with clarity as low as I1 and I2 are quite visible and can affect the sparkle of the stone. When considering an SI2, try to see it in person or get a detailed report on the inclusions. I always like to get SI2’s in prior to buying and I will analyze the stone for you and give you my honest opinion of the stone as well as send along detailed images. There is a range in clarity grades and you can have a good SI2, a fair SI2 or a bad SI2. I have seen amazing SI2's that I think should be graded higher and I have seen terrible SI2's. It all depends on the size, type, color and placement of the inclusion. Most inclusions are small crystals that are included inside the diamond when it formed but some can also be an interruption in the growth structure, a natural imprint, or a minute enclosed fracture.

Image source: www.gia.edu

Image source: www.gia.edu

Cut: Cut is the only grading criteria that is a contribution from man. How well the diamond is cut determines how much sparkle it will have. Cut is measured by three things: the symmetry of a diamond’s facets, the proportions of the angles and how well the diamond has been polished. The better the angles, the more symmetrical and proportionate facets, the more optimal light return it will have, aka sparkle. A very good cut grade is a great place to be and "excellent" is the top cut grade. I wouldn't go any lower than "good.”

Cut is the biggest grading criteria that most people overlook- cut can make or break a stone. If a 1 carat diamond was a D color, VS1 clarity but has a fair to poor cut the stone can appear quite dim and not have any sparkle to it.

Image Source: www.gia.edu

Image Source: www.gia.edu

Shape: Shape is part of cut and helps define a diamond’s profile shape. Round is the most popular, but there is also princess cut (square), cushion cut (soft cornered square, looks like a pillow), oval, emerald, old European, marquise and pear as well as a few others. When you are considering a shape other than round, the cut grade is not as applicable since GIA’s grading system is modeled for a round brilliant cut diamond.


Other do’s and don’ts:
-Avoid diamonds with strong fluorescence. According to GIA, fluorescence does not affect the appearance of the stone[1] but this is debatable. When viewing a diamond with strong fluorescence indoors, it may appear no different than a stone without fluorescence. If you take that diamond outside to view it in sunlight, the diamond with strong blue fluorescence will appear very cloudy and look smudged despite how many times you try to wipe it clean. Additionally, often times when you view two diamonds that are equal in all ways except for fluorescence, the stone with the stronger fluorescence will be priced lower than the one without. This is usually a good indication that the fluorescence contributes to the appearance of the diamond. That being said, sometimes a warmer colored diamond, like a J or K with faint fluorescence can actually be a benefit. The diamond may appear whiter because the blue tint from fluorescence cancels out the warmth tone. This varies stone to stone so it is always important to see a stone in person before purchasing it or having a professional give you their personal and honest opinion. 

 -Avoid diamonds with EGL reports. The 4 C’s grading system was invented by GIA but many other certification institutes use it as well. EGL is a lab that uses the 4C’s grading system but often misuses it and grades higher than what the diamond actually is. They most commonly do this in color since they grade the diamond in the face up position, rather than the intended face down position, as instructed by GIA. For example, they may give an I color diamond a G grade. When you are searching for diamonds and you come across this G graded diamond by EGL, the price may seem like a great deal. However, if you go to get this appraised in the future, it will appraise for less than what you paid and will be reassigned the correct color grade.

 -Consider clarity inclusions as a benefit and remember your diamond’s inclusions. No two diamonds are alike. Your diamond’s unique inclusions can always help you identify your stone. This is great if you are taking your diamond ring to a new jeweler for service or repair. Knowing your diamond’s inclusions and where they are located can help ease your nerves when you drop off your diamond for the first time.

Congratulations! You are now a diamond pro. Even if you don’t feel like one yet, you now have some knowledge to start with in your search for the perfect diamond.

Still have questions? Please shoot me an e-mail! I am a certified Graduate Gemologist through GIA and love to answer any questions.


[1] http://www.gia.edu/gems-gemology/winter-1997-fluorescence-diamonds-moses