Understanding the 4Cs of Diamonds: A Guide to Choosing the Perfect Stone

Selecting the Diamond for something as lasting as jewellery is an important decision, especially when it comes to searching for engagement rings, bridal jewellery, and other family heirlooms. In these cases, it is also seen as a timeless gesture that marks a new chapter in a story and conveys a depth of emotions beyond words. 

To choose the perfect Diamond with confidence and discernment, knowing the 4Cs of Diamonds is helpful. Developed by the Gemological Institute of America (GIA), this globally recognised standard for evaluating Diamonds provides a universal language for assessing and grading a Diamond's value: Carat, Cut, Clarity, and Colour.

Whether you are looking for the perfect Diamond engagement ring or a magnificent anniversary gift, this guide will explore the fundamental principles of a Diamond's quality and worth so you can confidently select a Diamond.

The First "C" — Carat

Carat refers to the Diamond's weight; not its physical size, although the two are often related. The term "carat" originated from the carob seed, which ancient traders used as a standard for weighing gemstones due to their uniform size.

Today, one metric carat is precisely 200 milligrams, or one-fifth of a gram. Different cuts also make a difference in how a Diamond’s size appears. 

For example, our Horizon Timeless Diamond Ring features a 1.01ct Round Brilliant Diamond:

Our High Street Diamond ring which features a 1.02ct Old Mine Cut Diamond: 

Our Jazz Age Fifth Avenue Diamond Ring features a 2ct Emerald Cut (Step Cut) Diamond:

For Diamond engagement rings, carat weights from 0.50 to 2.00 carats draw a lot of attention for practical reasons – this size offers versatility and ease of wear, for something that most people wear daily.

As a natural Diamond's carat weight increases, especially paired along with other characteristics its price tends to rise too. Larger gem-quality natural Diamonds are much rarer.

While a larger carat weight may be a priority for some, choosing the right Diamond carat often involves finding a harmonious balance, allowing you to invest in a stone that not only has a stunning presence but also possesses exceptional diamond quality in the other Cs.

The Second "C" — Cut

Of all the 4Cs of a Diamond, the cut is often considered the most important, as it directly impacts a Diamond's brilliance, fire, and scintillation (the sparkle and light it emits). Many might believe that that "cut" refers to the Diamond's shape (such as round or cushion). The cut refers to the proportions, symmetry, and polish of the Diamond's facets.

A masterful Diamond cut allows light to enter the stone, reflect off its internal surfaces, and disperse back through the top, creating that dazzling play of light. The facets, known as the crown, table, girdle and pavilion and culet, are arranged with precise mathematical proportions to maximise a Diamond's fire, life and brilliance. The GIA and other reputable laboratories assign a cut grade to a Diamond, in this order from best to worst:

• Excellent: The highest grade, representing a Diamond masterfully cut for maximum brilliance and fire. B.P. de Silva’s Diamonds are graded Excellent cut.
• Very Good: Reflects a high percentage of light, offering exceptional sparkle at a slightly more accessible price point.
• Good: Reflects a decent amount of light but with less brilliance than higher grades.
• Fair: A cut that reflects a small amount of light, resulting in a noticeably dull appearance.
• Poor: A cut that reflects very little light, making the Diamond appear lifeless and lacking in sparkle.

Interestingly, with expert craftsmanship, a well-cut Diamond can actually appear more brilliant and fiery than a poorly cut Diamond of the same carat.

The Third "C" — Clarity

The third C of Diamond grading, clarity, refers to the absence of internal inclusions (internal flaws) and external blemishes (surface flaws). As Diamonds are formed naturally within the Earth under immense pressure and heat, these imperfections are often an inevitable part of their unique story.

The GIA's Diamond grading system for clarity ranges from:

• Flawless (FL): No inclusions or blemishes are visible under 10x magnification.
• Internally Flawless (IF): No inclusions are visible, but minor blemishes are present.
• Very, Very Slightly Included (VVS1, VVS2): Inclusions are so minute that they are difficult for a skilled grader to see under 10x magnification.

B.P. de Silva only crafts with Diamonds of the finest clarity grades: FL to VS2.

• Very Slightly Included (VS1, VS2): Inclusions are minor and visible with effort under 10x magnification.
• Slightly Included (SI1, SI2): Inclusions are noticeable under 10x magnification and may be visible to the naked eye.
• Included (I1, I2, I3): Inclusions are obvious under 10x magnification and are often visible to the naked eye.

The Fourth "C" — Colour

In white or colourless Diamonds, colour refers to the absence of colour. These types of Diamonds are rare as they come from pure geological formations that are free from any and all trace elements. Hence, the more colourless a Diamond is, the more coveted and valuable it is.

The GIA's Diamond grading scale for colour ranges from D to Z.

• D-F: Colourless. These are the rarest and most valuable in the world or white, or colourless Diamonds. B.P.’s Diamonds fall within this colour grade, with the only exceptions beyond Fancy Coloured Diamonds.

• G-J: Near Colourless. These Diamonds show very little colour and can appear colourless to the naked eye, especially when set.
• K-M: Faint Colour. A faint yellow tint is visible.
• N-R: Very Light Colour. A light yellow tint is visible.
• S-Z: Light Colour. A noticeable yellow or brown tint is visible.

A Diamond's colour can significantly affect its brilliance since a Diamond with a noticeable yellow tint can absorb light and affect its scintillation sparkle.

Fancy Coloured Diamonds, however, are an exception to the Colour Grading mentioned above. Colour evokes emotion, and Coloured Diamonds are no exception with their different unique hues making them an irresistible treat for gem collectors and jewellery aficionados.

Beyond the 4Cs

While the 4Cs provide the essential framework for evaluating a Diamond, other factors contribute to its overall beauty and value:

• Shape: A Diamond's shape (e.g., round, oval, hexagon, marquise) is a matter of personal preference and style. A round brilliant is the most popular, renowned for its unparalleled brilliance, while other shapes offer a more unique aesthetic.
• Fluorescence: Fluorescence is the glow emitted when a Diamond is under ultraviolet light. While it can be a concern for some, in many cases, it has no impact on a Diamond's appearance.
• Certification: A reputable Diamond grading report from an independent laboratory like the GIA, detailing the Diamond's specific 4Cs and other characteristics, provides reassurance, too. It guarantees its authenticity and quality, offering peace of mind and confidence in your jewel.
• Jeweller Expertise: The most critical factor beyond the Diamond chart is the jeweller you choose. Having served clients for over 150 years, at B.P. de Silva, our experienced Jewellery Specialists are happy to provide expert guidance, helping you find a Diamond that aligns with your desires and budget.

A Confident Choice

Understanding the 4Cs of Diamonds empowers one to make a confident decision and prioritise the factors that matter most to you.

At B.P. de Silva, our Jewellery Specialists are dedicated to helping you secure the perfect creation. We believe that choosing a Diamond should be a joyous and memorable experience. Whether you're seeking a piece from our exquisite collections or wishing to commission a truly unique custom engagement ring or other custom jewellery, we are here to help.

Visit our flagship boutique or book a virtual concierge appointment today to experience the brilliance of our Diamonds firsthand.