Learn About DIamond & Jewellery

The 4Cs Of Diamonds

The 4Cs of Diamonds - cut, color, clarity, and carat weight - the most important characteristics to understand when making a diamond purchase.

Cut

The most important of the 4Cs is cut because it has the greatest influence on a diamond's sparkle.

Color

The second most important of the 4Cs is color, which refers to a diamond's lack of color. The less color, the higher the grade.

Clarity

Often the least important of the 4Cs because the tiny imperfections are often microscopic.

Carat Weight

The term carat actually refers to the diamond's total weight and not its size.

What Is The Cut Of A Diamond?

Have you ever noticed how many surfaces a diamond has? A diamond’s cut refers to how well-proportioned the dimensions of a diamond are, and how these surfaces, or facets, are positioned to create sparkle and brilliance. For example, what is the ratio of the diamond’s diameter in comparison to its depth? These small, yet essential, factors determine the diamond’s beauty and price.

Are You Wondering Which Diamond Cut Is Best? It All Starts With Your Budget.

No single diamond is perfect for everyone—but all of our customers, whether they’re eyeing a .50-carat or a 16-carat diamond, want as much sparkle as their budget allows. Of the the 4Cs (cut, color, clarity, carat), cut has the greatest influence on a diamond’s beauty and sparkle. Even a diamond with a flawless clarity grade (no blemishes or inclusions) can look glassy or dull if the cut is too shallow or deep. So, when determining what diamond to buy, go with the best cut grade that you can afford.

Grading Scale

See cut grade details or view the Cut Grade Chart below.

The Characteristics Of A Well-Cut Diamond Are Superior Brilliance, Fire, And Scintillation

Brilliance relates to the reflection of white light

Fire is the dispersion of light into the colors of the rainbow

Scintillation is the play of contrast between dark and light areas—it’s the sparkle

The Anatomy Of A Diamond:

Table: The largest facet of a gemstone

Crown: The top portion of a diamond extending from the girdle to the table

Girdle: The intersection of the crown and pavilion which defines the circumference of a diamond

Diameter: The measurement from one girdle edge of a diamond straight across to the opposing side

Pavilion: The bottom portion of a diamond, extending from the girdle to the culet

Culet: The facet at the tip of a gemstone. The preferred culet is not visible with the unaided eye (graded "none" or "small")

Depth: The height of a gemstone measured from the culet to the table

Diamond Cut And Diamond Shape Are Not The Same Thing

Although these terms are sometimes used interchangeably, diamond cut, and diamond shape mean different things.

Diamond cut assesses light performance of a diamond and is based on a combination of factors: proportions, symmetry, and polish (the overall surface condition of a diamond’s facets).

Diamond shape is related to the outline of a diamond. While the round brilliant diamond is our most popular shape, we also offer nine non-round fancy-shaped diamonds that can save you up to 25%.

What Is The Most Expensive Cut Of A Diamond?

When people talk about someone’s engagement ring, everyone focuses on carat. In reality, it’s the cut of the diamond that can be the biggest factor in the price tag. The Ideal cut diamond, and the super-ideal Astor by Blue Nile™, are the most expensive diamond cuts because they optimize light performance and create the most impressive sparkle.

What Is Diamond Color?

Did you know that it’s very rare to find a diamond that doesn’t have any color at all? In fact, diamonds are found in almost any naturally occurring color, including gray, white, yellow, green, brown, and pink.

Some General Info About Diamond Color

Part of diamond valuation is determined by the absence of color.

Only certified grading professionals should determine a diamond’s color grade.

The tone of a ring’s setting can affect the appearance of diamond color.

Diamond Color Is An Important Characteristic That Affects A Diamond’s Beauty

Like all of the 4Cs, diamond color is an important consideration when buying a diamond. While color affects price, there are a number of factors that can help you decide which color grade is right for you.

The GIA White Diamonds Color-Grade Scale Is The Industry Standard

The Gemological Institute of America (GIA) color scale is the industry standard for diamond grading. The GIA diamond color grades range from D (colorless) to Z (light yellow or brown). Many people ask why the GIA diamond grading scale starts at D. Arcane systems used grades of A-C, 1-3, and I-III, etc. The GIA set out to standardize these diverse systems and started their scale fresh with a grade of D.

D Color Diamonds (Absolutely Colorless)

D color diamond is the highest grade and is extremely rare—the highest color grade that money can buy. Eight percent of customers choose a D color diamond.

Are You Wondering Which Diamond Color Is Best? It All Starts With Your Budget.

The absence of color in a diamond is the rarest and therefore, the most expensive. While the majority of our customers choose a D or E color grade, many go with a beautiful near colorless grade to make the most of their budget and allocate more on the best cut that they can afford (which gives them more sparkle).

Deciding whether or not you want to spend more on diamond color grade is partly related to the size and shape of the diamond that you are considering, and your setting preference. You can save by knowing how color affects these attributes.

Color Is More Visible In Large Diamonds

If you’re buying a diamond under 1 carat, you might consider choosing an I, J, or K color diamond. Going over 1 carat? We recommend H color-grade diamonds or higher.

Recommendations For Diamond Color Based On Shape And Setting

Certain fancy-shaped diamonds hide color better than others—and can cost up to 25% less than a round-cut diamond. It’s also smart to consider the color of precious metal for your setting that best compliments the color grade of your diamond. For example, yellow gold casts a warm glow and looks best with diamonds with faint color. Platinum or white gold will make a near-colorless diamond look icier.

The Difference Between White Diamonds And Fancy Colored Diamonds

When is color a good thing? As mentioned before, diamonds occur in the natural rainbow spectrum of colors—red, orange, yellow, green, blue, pink, purple, and more. These are known as colored diamonds. Only 1 in every 10,000 diamonds possess natural color, and the more intense the color, the rarer and more valuable the diamond. Fancy-colored diamonds are graded on a separate color scale and can be even more valuable than white diamonds.

What Is Diamond Clarity?

Diamond clarity is the assessment of small imperfections on the surface and within the stone. Surface flaws are called blemishes, while internal defects are known as inclusions. In most cases, a diamond’s beauty is not affected by these in any way since most inclusions can’t be seen with the naked eye. When referring to inclusions, gemologists often use the term “internal characteristics” instead of flaws. Internal characteristics are what give a natural diamond its character. It’s also important to note that diamonds with the fewest and smallest inclusions receive the highest clarity grades—and higher price tags to reflect that.

Remember, all diamonds are unique, not perfect. They are made underground through enormous pressure and heat. Natural inclusions and blemishes are inevitable.

Quick Clarity Tips

There are many misconceptions around the clarity of diamonds, including the belief that you need to buy a high clarity grade to avoid seeing imperfections. Another common falsehood is that a higher clarity grade results in more sparkle. Neither of these is true! Here are some tips to get you started on your diamond search:

The term “eye clean” means that the diamond’s inclusions are too small to see without magnification.

A good place to start your search and maximize your budget is with Slightly Included (SI) and Very Slightly Included (VS) grades because inclusions will not be readily noticeable without magnification.

Diamond shape and size affect clarity. While clarity is less important than a diamond’s cut or color, if you are buying a diamond over one carat or considering certain fancy-shaped diamonds (like an emerald or Asscher cut where flaws are more visible), you may want to spend more for a higher clarity grade.

Diamond clarity is an important characteristic that affects a diamond’s beauty. Like all of the 4Cs, diamond clarity is an important consideration when buying a diamond. While clarity affects price, there are a number of factors that can help you decide which clarity grade is right for you.

Diamond Clarity Spans 6 Categories With A Total Of 11 Clarity Grades

In 1953, Richard T. Liddicoat and colleagues established the Gemological Institute of America (GIA) diamond grading system and clarity scale. The GIA diamond grading scale is divided into 6 categories and 11 diamond clarity grades.

I1, I2, I3 Included Diamonds

I clarity diamonds have obvious inclusions that are likely to be visible and impact beauty

Blue Nile does not sell I clarity grade loose diamonds for engagement ring designs

Blue Nile does offer a limited selection of jewelry preset with I1 diamonds

SI1, SI2 Slightly Included (SI) Diamonds

Inclusions are noticeable at 10x magnification

If eye clean, SI diamonds are often the best value

SI2 inclusions may be detectable to a keen unaided eye, especially when viewed from the side

VS1, VS2 Very Slightly Included (VS) Diamonds

Minor inclusions ranging from difficult (VS1) to somewhat easy (VS2) to see at 10x magnification

Great value; Blue Nile’s most popular diamond clarity

VVS1, VVS2 Very, Very Slightly Included (VVS) Diamonds

VVS diamonds have minuscule inclusions that are difficult even for trained eyes to see under 10x magnification

VVS clarity is rare and results in an eye clean appearance

Characteristics are minuscule and difficult to see under 10x magnification, even to a trained eye

Internally Flawless (IF) Diamonds

Some small surface blemishes may be visible under a microscope on IF diamonds

IF diamonds have no inclusions within the stone, only surface characteristics set the grade

Visually eye clean

Flawless (FL) Diamonds

No internal or external characteristics

Less than 1% of all diamonds are FL clarity

A flawless diamond is incredibly rare because it’s nearly impossible to find a diamond 100% free of inclusions

Diamond Clarity Scale

Have a look to compare diamond clarity

Flawless (FL) Diamonds

Inclusions and blemishes aren’t visible on flawless diamonds, even under 10x magnification. Less than 1% of all diamonds are FL clarity. A flawless diamond is incredibly rare because it's nearly impossible to find a diamond 100% free of inclusions. Six percent of customers buy FL diamonds.

The Five Diamond Clarity Factors

Size: The larger or more noticeable a characteristic, the lower the likely clarity grade.

Number: This is the number of easily seen characteristics. Having fewer characteristics means a higher clarity grade.

Position: What is the position of any given characteristic? Is it under the table (most visible) and close to a pavilion? This position turns inclusions into reflectors, which have a bigger impact on the clarity grade.

Nature: The nature of a diamond characteristic relates to the type of inclusion and its impact on durability.

Color and relief: Color and relief are essentially a measure of how easily a characteristic is seen, or how much contrast there is between the characteristic and surrounding diamond.

Why SI Diamonds And VS Diamonds Are The Best Value

While the extremely rare Flawless (FL) or Internally Flawless (IF) diamonds are the highest quality diamond clarity, you may want to consider a diamond that won’t break the bank. For the best value, select a diamond with inclusions that can’t be seen through the crown without magnification (also known as eye clean diamonds), like a diamond with an SI or VS clarity grade. These diamonds are much less expensive and look the same as the higher grades, visually.

Diamond Shape

Some diamond shapes require a higher clarity grade than others. Emerald and Asscher-shaped diamonds (referred to as step cut) are designed with rectangular facets that emphasize transparency and let you see farther down into the diamond, which can make inclusions more visible. For these diamond shapes, choose a clarity grade of VS1 or better to ensure that the inclusions will not be visible.

Conversely, round, princess, oval, marquise, pear, and heart-shaped diamonds may not require as high of a clarity grade. Cut with a brilliant facet pattern, which reflects light from many different angles, these shapes naturally hide many inclusions.

Diamond Size

As diamond size increases, the size of the facets (the multiple mirror-like surfaces on the diamond) become more abundant. This can make inclusions more visible. Be sure to prioritize a higher clarity grade as the size of your diamond goes up.

The Diamond Clarity Plot

Clarity plots are diagrams that show the location of clarity characteristics—mapping the blemishes on a diamond’s surface and the inclusions within a diamond’s interior. The inclusions are identified by a certified diamond grader using a device with 10x magnification.

You Can Learn More About A Diamond’s Characteristics (Inclusions/Blemishes) In The GIA Grading Report

Any characteristics that don’t get factored into the diamond’s assigned grade may still be noted on the GIA grading report or clarity plot (if there is one). As is common practice in the industry, you’ll only find a clarity plot when the diamond is over one carat.

There Are Many Different Types Of Diamond Inclusions And Blemishes

If you find the whole topic of internal and external diamond characteristics as fascinating as we do, take a deep dive and learn more about the various types of inclusions and blemishes in your diamond of interest.

Types Of Diamond Inclusions

• Clouds
• Feathers
• Crystals or minerals
• Knots
• Cavities
• Cleavage
• Internal graining

Types Of Blemish Examples

• Polish lines
• Scratches
• Nicks
• Pits
• Chips
• Breaks
• Dark or light spots

What Is A Diamond Carat?

The term carat is often misunderstood. It refers to a diamond's weight, not its size. Another misperception is that a larger carat weight is always better than a smaller carat weight. While it’s true that a big rock can be a status symbol (here’s looking at you, Hollywood), carat weight is not related to sparkle. Beautiful sparkle is the result of a well-crafted cut. In fact, a high carat weight diamond with a poor cut may look smaller than a diamond with a smaller carat weight and a very good cut.

Diamond Carat Price

Diamonds with higher carat weights are cut from larger rough crystals that are harder to source than small crystals. So, the relationship between carat weight and price depends on the rarity or availability of a rough crystal. Carat price is also a function of finding rough crystals with desirable color, and internal and external characteristics that will positively influence clarity when the diamond is cut. To learn more about all of the factors to consider when choosing the best diamond carat weight for you, read these tips from our diamond experts.

The Brief History Of Diamond Carat

The term carat comes from the ancient method of weighing precious metal and stones against the seeds of the carob tree—which were considered to be even in weight. It wasn’t until 1907, at the Fourth General Conference on Weights and Measures, when it was agreed upon that one diamond carat would be equal to 200 mg, or .2 grams, of a diamond. Carats can also be measured in points; 100 points equals a full carat.

4 Things To Know About Carat

“Buy shy” to save money. Select a carat weight slightly below the whole and half-carat marks. For example, instead of a 2.00 carat diamond, consider buying a 1.90 carat weight. This will save a considerable amount of money, and the slight difference will never be noticed.

Splurge on cut. This is the most important factor because it maximizes sparkle. Even a high-carat diamond with excellent color and clarity can appear lifeless and dull if the cut is poor.

Fancy shapes cost less per carat. The most important thing to realize about fancy-shaped diamonds is that they are generally less expensive than an equivalent round diamond. Additionally, fancy shapes can appear larger than their actual diamond carat weight size, especially when placed in a halo setting.

Keep ring size in mind. The smaller the finger, the larger the diamond will appear. A 1.50 carat diamond solitaire looks larger on a size 6 finger than a size 8.

Carat Has The Biggest Effect On Price

You can thank movies, mass media, and advertising for the emphasis that people put on carat in relation to diamond quality. Carat weight has become an indication of a person’s status and wealth, but when it comes to diamonds, bigger is definitely not always better. Instead, focus on a balance of the 4Cs: cut, clarity, color, and carat to make a smart purchase.

Diamond Carat Size Chart

This chart illustrates how diamonds of different carat weights and shapes will appear when viewed from the top down. Your diamond measurements may differ from the chart in length/width ratio, table, and depth.

A Few Additional Carat Tips Before You Buy A Diamond

Certain settings can make a diamond appear larger. A very popular setting to achieve this effect is the halo. This setting has a ring of small diamonds around the center stone. The ratio of the small to large diamonds skews the perspective in your favor, making the center diamond seem larger.

Band size affects the look of a diamond’s carat. Selecting a thin band creates a perspective that makes the center stone appear larger. A popular band to achieve this is the pavé, which features small diamonds embedded in the band.

Carat Total Weight (CTTW). Total carat weight is the measurement of all the diamonds in any given piece combined. So, be sure to inquire about the weights of the individual diamonds in any piece that you are buying.

Diamond Carat Price Chart (Approx)

What Is A Lab-Grown Diamond?

Lab-grown diamond technology for industrial uses has been around for over 50 years, but within the last decade there have been impressive developments in quality and price, meaning these lab-grown stones can now be used in jewelry, too. Altering the “recipe” in the lab also means that lab-grown diamonds are available in different colors, including beautiful blues and pinks.

What Are The Benefits Of Lab-Grown Diamonds?

Are Lab-Grown Diamonds Real Diamonds?

Laboratory-grown diamonds and natural diamonds both consist of pure carbon in the same cubic crystalline form. The difference between lab-grown diamonds and natural diamonds can be distinguished by an expert using a high-tech machine—but not by the naked eye.

What’s The Difference Between Lab-Grown Diamonds And Natural Diamonds?

Both mined and lab-grown diamonds are made of pure carbon that is transformed into sparkling cubic crystalline stones. While their chemical foundation gives lab-grown diamonds the same optical properties as natural diamonds, lab-grown diamonds have no intrinsic rarity. Formed over millennia, natural diamonds acquire their scintillating shapes from the pressure of being compacted deep within the earth’s crust. Because of this, all of the natural diamonds that will ever exist have already been created making them forever rarities. Laboratory-grown diamonds, on the other hand, can be produced limitlessly.

Are Lab-Grown Diamonds Available In Different Colors?

Lab-grown diamonds come in a wide array of hues—whether you’re looking for a stone that’s classic white, blushing with pink, or as beautifully blue as a cloudless sky.

TakatGem offers an exclusive assortment of lab-grown diamond jewelry from Lightbox. Lightbox creates their beautiful colored stones by adding a gas mix to the CVD reactor and combining this with treatments that are incorporated at the end of the synthesis process. The result is stones rich with color, which would be extremely rare and expensive in natural diamonds.

How Are Lab-Grown Diamonds Made?

It all starts with a seed. Made from a tiny lab-grown diamond, the seed follows one of two processes: CVD or HPHT. Chemical Vapor Deposition, or CVD, takes the seed and puts it into a plasma reactor chamber where a mix of carbon-rich gasses are added at very low pressure. Microwaves are then introduced to heat the gasses and generate plasma. As the temperature climbs over several thousand degrees, the gas molecules break apart, making way for carbon atoms to bond to the seed one layer at a time.

The High Pressure High Temperature (HPHT) method mimics the conditions of natural diamond creation by placing seeds in a large mechanical press and applying extreme pressure and high temperature to the carbon that is present. The seed acts as a guide for the lattice of carbon (that will soon become the diamond) to grow layer by layer within a matter of days until the desired carat weight is achieved.

What Is The Difference Between Lab-Grown And Simulated Diamonds?

Unlike lab-grown diamonds, simulated diamonds are not diamonds. While they have a similar appearance to diamonds, simulants are made from seed materials like glass or cubic zirconia. This fact makes diamond simulants like moissanite lack the hardness and optical properties of lab-grown diamonds. As time goes on, simulants become much more susceptible to wear-and-tear and diminished sparkle.

How Are Lab-Grown Diamonds Certified And Graded?

Some lab-grown diamonds undergo grading and certification similar to natural diamonds by adhering to the the 4Cs of cut, clarity, color and carat. After being sent to a gem lab that specializes in grading diamonds, lab-grown diamonds are graded independently by several of the lab's gemologists. Afterward, the individual grades are compiled and compared to give the lab-grown diamond its final grade.

Can You Tell The Difference Between Lab-Grown Diamonds And Natural Diamonds?

Yes. The difference between lab-grown and natural diamonds can always be detected by a diamond expert with specialized technical equipment.

When purchasing Lightbox lab-grown diamond jewelry on our site, the quality is guaranteed by the presence of a tiny inscription. Because Lightbox lab-grown diamonds have the same sparkle and visual characteristics as a natural diamond, the presence of this inscription makes it easier to identify lab-grown diamonds larger than 0.2ct and confirms that the stones were manufactured by Lightbox and meet their high quality standards. This inscription is invisible to the naked eye but it can easily be seen with a 10X magnifying loupe.

Are Lab-Grown Diamonds Priced Differently Than Natural Diamonds?

Unlike the price of natural diamonds, which is determined by a stone’s unique characteristics and rarity, lab-grown diamonds can be priced uniformly per carat. Lab-grown diamonds also have the benefit of being priced significantly lower than natural diamonds since their production capacity is unlimited.