Welcome to Gemstone Foundations: MODULE 2
THIS MODULE INCLUDES:
Understanding the 4Cs
Discover what graders look for when valuing a gemstone
Clarity
See how a gemstone’s clarity affects its overall value
Carat Weight
Find out what carat weight means, and why size doesn’t always matter!
Cut
Uncover the importance of how a gemstone is cut
Colour
Explore the different ways in which colour can affect a gem’s value
Additional Information
Learn the differences between grading Diamonds and coloured gemstones
Understanding the 4Cs
When determining a Diamond’s overall quality and value, the industry relies on the Four Cs - a system created by the Gemological Institute of America (GIA). The Four Cs stand for: Clarity , Carat Weight , Cut , and Colour .
The Four Cs is a universal system designed to bring consistency to Diamond grading – essentially, it helps both buyers and jewellers speak the same language.
No two Diamonds are identical, and so many factors influence their beauty and value. The Four Cs breaks things down into clear categories, making it easier to understand why one Diamond might sparkle a little brighter, appear a little whiter, or carry a higher price tag than another.
Though other grading systems are used for coloured Diamonds and other coloured gems, the Four Cs apply specifically to colourless Diamonds.
Clarity
Clarity is all about how ‘clean’ a Diamond looks. Almost every Diamond has tiny natural features on both the inside (called inclusions) and the outside (called blemishes). These are like little birthmarks from its time spent forming deep within the Earth.
The fewer of these features you can see (especially under 10X magnification), the higher the clarity grade and, usually, the higher the value.
But here’s the secret: most inclusions are so small they’re invisible to the naked eye! So, while flawless Diamonds are incredibly rare – and in lots of cases, expensive – many Diamonds with lower clarity grades still look beautifully clear and sparkly in everyday life.
Clarity Chart
FL: Flawless
IF: Internally Flawless
VVS: Very Very Slightly Included
VS: Very Slightly Included
SI: Slightly Included
I: Included
Diamond
Carat Weight
Carat weight is simply a way of measuring how heavy a Diamond is, and in turn, how big it looks. One carat equals 0.2 grams – roughly the same as a paperclip!
Because larger Diamonds are rarer, their price rises as the carat weight increases. But bigger doesn’t always mean better; a smaller Diamond with an excellent cut can sparkle far more brilliantly than a larger one that’s poorly cut, and be deemed more valuable because of this.
Carat weight is just one piece of a much larger puzzle. The real magic comes from finding the balance that feels right for you – size, sparkle, and overall beauty together.
Cut
Cut is often called the most important of the Four Cs because it’s what brings a Diamond to life!
While people sometimes think ‘cut’ just means shape (like round, oval, or princess), it’s also about how well the stone has been faceted and polished.
Facets are the flat, angled surfaces cut into a Diamond; they’re like tiny mirrors that catch and reflect light. When these facets are arranged perfectly, light bounces around inside the stone and shoots back out, creating that brilliant sparkle and rainbow fire we know and love. But if the cut is too shallow or deep, the light escapes, leaving the Diamond looking dull, no matter how big or clear it is.
In other words, the way a Diamond is cut is the secret to unlocking its full beauty and potential.
Colour
When we talk about colour in Diamonds, we actually mean the lack of it.
The most valuable white Diamonds are graded for how icy or ‘colourless’ they are, with the GIA scale running from D (totally colourless) through to Z (light yellow or brown tint). The less colour, the more valuable the stone.
That said, some people love a touch of warmth in their Diamond. Coloured Diamonds like pink and blue –known as ‘fancy’ Diamonds – are in their own category altogether, and graded by hue, tone, and saturation.
While a crisp, icy-white Diamond may be the classic choice, beauty is in the eye of the beholder – and every shade has its own personality and charm.
Diamond Colour Chart
Additional Information
The Four Cs grading system is a brilliant guide when it comes to Diamonds, but it’s not universal. It was designed specifically for colourless Diamonds, and not every gemstone can be judged by the same rules.
Each gem has its own unique qualities that make it special - colour might be the most important factor in a Sapphire, while clarity plays a bigger role in Emeralds. Rarity, beauty, and desirability can all mean different things depending on the stone.
So, while the Four Cs are perfect for Diamonds, remember: every gemstone writes its own rulebook when it comes to value.
Key Takeaways
Congratulations, you’ve completed the second module! Before you move on, here are some key takeaways from this section:
The Four Cs stand for Clarity, Carat Weight, Cut, and Colour
Clarity looks at the presence or absence of inclusions within a Diamond
Large carat weights are rare, but that doesn’t always make the gem more valuable
The amount of sparkle a Diamond has depends on how it’s cut
When grading white Diamonds, the most valuable stones have the least colour
Did you know???
Some Diamonds are older than life itself!
Formed deep within the Earth’s mantle one to three billion years ago, these natural treasures predate even the earliest fossils. This means that the Diamond in your ring could be twice as old as life on Earth.
Fancy 20% off your next Gemporia purchase? That’s what you’ll receive when you complete the course!
Gem Expert Progress Board
Here are the badges you’ve earned – and the ones still waiting for you.
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Let’s go deeper into the world of gems!