Diamond Grading Guide: What To Know About the Diamond Grading Scale

If you’ve been looking into purchasing a diamond, you’ve likely heard about diamond gradings scales. However, hearing about them and understanding the diamond grading scales are two very different things.

There are many different factors affecting a diamond, and understanding what they are and what is considered desirable are good tools to have when shopping around.

In our diamond grading guide, we’ll discuss everything you need to know about understanding diamond grading scales, including diamond colour grading, diamond clarity grading, diamond cut grading and diamond carat weight grading. We’ll also discuss the origins of the diamond grading system and the different diamond grading charts. Read on to learn all you need to know about diamond grading scales before heading out to a diamond jewelry store in Toronto.

Origins of Diamond Grading Scales

It’s hard to believe, but diamonds were not always as popular as they are today. In previous centuries, colourful gemstones like sapphires, rubies and emeralds were highly desired and are often seen in ancient royal jewelery.

While diamonds have also been used in jewelery for centuries, it wasn’t until the 1940s that diamonds surged in popularity as an engagement ring stone due to the ‘A Diamond is Forever’ advertising campaign. While there were many different methods used for diamond grading, there was no universally used way to grade or compare diamonds from one jeweler to another, leading to much confusion.

In 1953, the Gemological Institute of America created the 4Cs as universal benchmarks to judge the quality of any diamond. This allows people purchasing diamonds to understand what they are buying and how it is priced.

While other institutes have different benchmarks for their own diamond grading scales, the GIA scale is the principal criterion for grading a diamond and is the most commonly used throughout the industry.

It’s important to recognize that these diamond grading scales are solely for colourless diamonds. The same methods used for grading a diamond are not used for fancy diamonds or alternatives to diamond engagement rings.

Diamond Grading Explained

Understanding diamond grading is extraordinarily helpful when shopping for diamond engagement rings in Toronto. Here is everything about diamond grading explained.

The diamond grading scales centre around the 4Cs. Each of the Cs is measured differently and has a diamond grading chart to illustrate the differences between each grade.

Diamond Colour in Grading

The GIA diamond colour grading scale rates diamonds from D to Z, with D to F rated as colourless, G to J are near colourless, K-M are faint, N-R are very light, and S to Z are light. All diamonds rated from D to Z are considered within the normal colour range of diamonds.

When talking about diamond colours in terms of diamond grading scales, it’s important to note that we are talking about colourless diamonds. With colourless diamonds, the scale is based on the absence of colour, as this represents chemical purity and structural perfection. Whereas with fancy or coloured diamonds, the higher value is placed on diamond colours with more intense and vivid colours.

Diamond Clarity in Grading

The GIA diamond clarity grading scale is difficult to understand without understanding how diamonds are formed. When carbon is exposed to intense heat and pressure in the earth’s mantle, its results in natural diamonds. As diamonds are created throughout this process, internal characteristics known as inclusions and external characteristics known as blemishes can occur.

There is no such thing as a perfectly pure diamond, but the purer it is, the better the clarity. While many of the blemishes and inclusions are so small that they aren’t noticeable, they do impact the overall quality of the diamond.

The diamond clarity grading chart rates diamonds as flawless (FL), internally flawless (IF), very very slightly included (VVS1 and VVS2), very slightly included (VS1 and VS2), slightly included (SI1 and S!2), and included (I1, I2 and !3).

Diamond Cut in Grading

Diamond cut and diamond shape are commonly mixed up. A diamond shape is simply the shape the diamond has been cut into, for example, round, princess, oval, etc. Diamond cut refers to the way the facets interact with light. The cut is responsible for the overall shine and beauty and is how diamonds get their sparkle and brilliance.

When a diamond is well cut, light enters through the top to the end, where it then reflects from one side to the other and finally back out through the top and into the eye of the observer.

The GIA diamond grading system for diamond cut ranks them as excellent, very good, good, fair or poor.

Diamond Carat Weight in Grading

Another commonly misunderstood C, diamond carat is often mistaken for its size. However, carat is the international standard for determining a diamond’s weight. A carat is equal to 200 milligrams. Larger diamonds are rarer than small ones, making them more expensive. However, it’s important to note that carat weight increases, flaws in the cut, clarity and colour are more obvious.

Whether you’re looking for a diamond engagement ring or want to get a permanent bracelet welded in Toronto, we can help! Come by our shop to browse or chat or reach out to us by phone or email.

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