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Diamond Basics: A No-Nonsense Guide 

So, you’re thinking about getting yourself a diamond, but you’re feeling a bit overwhelmed with all the “Cs” – cut, carat, clarity, and colour. Don’t worry, we’ve got your back. In our diamond basics guide we’re going to break down what you really need to know about the 4C’s of diamonds. We’re also going to look into how the 4C’s (Cut, Carat, Clarity and Colour) relate to lab-grown diamonds because we know you have questions.

If you would like to learn more about lab grown diamonds specifically or even browse available stones for purchase, please visit this link.


Diamond Cut: The Sparkle Factor


First up, let’s talk about the “cut.” The cut of a diamond isn’t about its shape (like round, cushion, or pear). It’s about how well that diamond has been cut from the rough stone. The cut affects the diamond’s sparkle, and that’s what is really most important. In fact, we would argue that the cut is the most important “C” of the “4C’s”! The better the cut, the more light reflection you will get from your diamond.

Above is a summary graph of the GIA scale of diamond cuts. We recommend staying in the Excellent to Very Good range. From time to time you may also see diamond cuts described as ideal or super ideal. You may also come across other terms used to describe diamond cuts. These are all cut names that have been branded by companies. The highest cut grade is what we call triple excellent which refers to a diamond that has been graded excellent on cut, symmetry and polish by GIA.

If you’d like to go beyond the basics, please visit one of our partners, PT Diamonds, and learn more about diamond cut.

Diamond Cuts and Lab Grown Diamonds

Lab grown diamonds are graded using the exact same scale as earth mined diamonds. The grading reports will come from labs such as IGI, GCAL and now also GIA. The vast majority of lab grown diamonds are cut to either excellent or very good grades. We would recommend an excellent cut for your lab grown diamond.


Diamond Carat: The Size Factor

Next up in our diamond basics is carat. A lot of people think that carat refers to the size of the diamond. It does not. It refers to the weight of the diamond, measured in “carats”. The weight measurement for diamonds actually came from placing carab seeds on one side of a scale versus diamonds on the other. The cost was determined by on how many carab seeds equaled the weight of the diamond.

So, for example, a one carat diamond will not have a standard measurement in millimeters. For a properly cut stone, a one carat diamond can usually range in size from 6.3-6.6mm. As a basic rule, the larger the carat size, the larger the diamond.

If you’d like to go beyond the basics, please visit one of our partners, PT Diamonds, and learn more about diamond carat.

Diamond Carats and Lab Grown Diamonds

Because lab grown diamonds and earth mined diamonds are chemically identical, they weigh the same. So a carat weight of a lab grown diamond will be equivalent to a carat weight of an earth mined diamond. But, since lab grown diamonds have such a great price point, you will likely get more carats for your budget with a lab grown.


Diamond Clarity: What Can and Can’t be Seen


Clarity measures the tiny imperfections, or “inclusions,” inside the diamond. Think of these inclusions as the diamond’s natural birthmarks. They’re like its unique fingerprint. Clarity is graded from “Flawless” (no inclusions) to “Included” (inclusions you can see with the naked eye).

We recommend staying in the range between Flawless and SI1. Flawless and Internally Flawless are quite rare, so if you’re looking for a very clean stone then you’ll be fine with anything in the VVS1 to VS2 range. If you’re looking for a better price point you can also consider diamonds with a clarity grade of SI1. The category of SI is the lowest you can go in the clarity range before you can see the inclusions with your naked eye. We find that the inclusions in the SI1 category are usually less significant than the inclusions in the SI2 category.

Recently, heavily included diamonds have actually become quite popular. They have been rebranded as salt and pepper diamonds.

If you’d like to go beyond the basics, please visit one of our partners, PT Diamonds, and learn more about diamond clarity.

Diamond Clarity and Lab Grown Diamonds

Due to the fact that lab grown diamonds are made in a controlled environment, they typically don’t have as many inclusions as earth mined diamonds. Lab grown diamonds, on average, usually have a clarity grade between VVS1 and SI1.


Diamond Colour: Personal Preference

Our final “C” to cover in our diamond basics is Colour. In many ways colour is the least important of all of the C’s. That’s because the colour is the one “C” that gets affected by life. Diamonds love grease. Simply cooking or applying lotion will add a layer of grease to your diamond which will affect its colour. The colour of a diamond will also be affected by the build up of dirt and grit under the setting. Of course, it’s an easy enough fix to clean your diamond and have it looking like new again.

We recommend any colour between D and I or perhaps J. The one exception would be if you are planning to set the diamond in white gold or platinum. Sometimes a white metal can actually highlight the slight yellow undertone in a lower graded diamond. For white gold or platinum settings it’s best to stick with colours between D and H.

If you’d like to go beyond the basics, please visit one of our partners, PT Diamonds, and learn more about diamond colour.

Diamond Colour and Lab Grown Diamonds

As noted above, because lab grown diamonds are created in a controlled environment, it’s easier to produce colourless material. Most Colour grades of lab grown diamonds will be in the colourless (D, E, F) to near colourless (G, H, I, J) range.


Some Final Diamond Basics

  • diamonds are the hardest mineral but that does not mean they are indestructible
  • diamonds are not rare but naturally coloured diamonds are quite rare
  • their durability and light reflection make them ideal stones to use in jewellery that is worn everyday


We hope that you have found this guide useful but if you still have questions please get in touch with us, we’re happy to help!


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