The 4 C's of Diamonds: How to Use Them to Choose the Best Diamond

The 4 C's of Diamonds: How to Use Them to Choose the Best Diamond

Buying a diamond is an exciting process. Whether you’re proposing or are buying a diamond piece for your birthstone (don’t forget — April’s birthstone is diamond!), there are many reasons to buy and wear a new diamond.
Since diamonds are one of the most exquisite stones, it’s easy to be confused about quality and grading lingo.
When diamond shopping, it’s essential to know what to look for and understand quality as well as rarity. The best way to do this is by learning about the 4 C’s, or color, cut, clarity, and carat.
Here are the 4 C’s of diamonds and how to use them when shopping for a new diamond. Around the globe, this universal language describes diamond quality.


You often hear phrases such as “a 5-carat diamond” or “a 2-carat diamond.” But what do these phrases mean? They identify the carat size of a diamond. A carat is a measurement of weight and it’s an indicator of the overall diamond size.
In short, the larger the size, or larger the carat, the more value the diamond holds. In addition, larger carat diamonds are rarer than smaller carat diamonds.


The reason a diamond looks brilliant is because of its cut. When the diamond reflects white light you will be able to see the brightness of the diamond, which is also considered it's brilliance. The way white light travels through the diamond disperses it into a variety of spectral colors. When you rock and tilt the diamond, look for red, blue, yellow or orange flashes which is called "fire". Specific cuts attract more light than other cuts, hitting the diamond perfectly to maximize its beauty.
Only standard round brilliant cut diamonds have an actual cut grade assigned to them (from an accredited laboratory) which range from poor to excellent. Poor cuts cause light to leak out of the diamond, making the diamond look lifeless. Scintillation and pattern play a role, look for the reflections to appear balanced and even with the spots of light that flash. Also, look for a crisp, sharp contrast with no distracting dark areas.
How do you know if a diamond is well cut? It’s hard for a consumer to see the difference. The best advice is taking a few diamonds you want to buy and compare them side-by-side. Choose the one that has the strongest sparkle.


Higher-end diamonds look whiter with little to no color leaking in. Lower-quality diamonds have more color in them, specifically yellow and brown.  
The Gemological Institute of America, or GIA, has a useful diamond color classification chart.
The diamonds receive a letter grade, ranging from D to Z. The letter D means the diamond is colorless, Z means the diamond is light yellow or brown. Use this chart when selecting a diamond. Letter D through F is the most rare and valuable, this range is considered "colorless". The "near colorless" range, which is G through J, is considered by many people to be very desirable. The best thing to do is compare different color diamonds side by side.


All diamonds have imperfections, known as inclusions. Think of them as birthmarks — as the diamond grows, they develop unique characteristics, either internal (inclusions), or external (blemishes). These inclusions affect a diamond’s clarity.
The highest quality diamonds have less inclusions. In other words, the highest quality diamonds have better clarity since the inclusions aren’t clouding or blocking the diamond’s natural shine.
Clarity is graded by magnifying the diamond (with either a loupe or microscope) by 10 times and viewing the inclusions. When grading a diamond's clarity, the gemologist evaluates the size, nature, position, color or relief, and quantity of the inclusions. To see more details about the clarity scale, please visit:
Now that you know the 4 C’s of diamonds, are you ready to buy a diamond? Since no two diamonds will ever look the same (even if they're graded identical), it is always best to have the guidance of a trusted jeweler. If you’re located in the Tampa Bay area, contact Johnston Jewelers.
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