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The diamond cut is the most important element to consider when buying a diamond. The cut is the biggest factor in creating sparkle and fire, and without a high cut grade even a diamond of high quality can appear dull and lifeless. A diamond cut poorly and too deep can face-up smaller than it actually is.

The cut of a diamond not only refers to the diamond’s shape, it also refers to how effectively the diamond returns light back to the viewer’s eye. A well-cut diamond will appear very brilliant and fiery, while a poorly cut diamond can appear dark and lifeless, regardless of its color or clarity. Not only do well-cut diamonds appear more brilliant, they also tend to appear larger than other diamonds of the same carat weight. An ideal diamond has both increased brilliance and diameter relative to more deeply-cut diamonds.

Understanding Brilliance, Dispersion & Scintillation

A well-cut diamonds exhibit three different properties: brilliance, dispersion and scintillation. As light strikes a diamond's surface, it will either reflect off the table of a polished stone or enter the diamond. The light that is reflected off the diamond is known as the diamond's brilliance. As light travels through a stone, some of the light rays are separated into flashes of color. This is known as dispersion. The result of dispersion—the separation of white light into its spectral colors— is known as fire. Scintillation is flashes of color that are viewable as an observer moves a diamond back and forth.

Excellent

Excellent Cut Diamonds provide the highest level of fire and brilliance. Because almost all of the incoming light is reflected through the table, the diamond radiates with magnificent sparkle.

Very Good

Very Good Cut Diamonds offer exceptional brilliance and fire. A large majority of the entering light reflects through the diamond’s table. To the naked eye, Very Good diamonds provide similar sparkle to those of Excellent grade

Good

Good Cut Diamonds showcase brilliance and sparkle, with much of the light reflecting through the table to the viewer’s eye. These diamonds provide beauty at a lower price point.

Fair

Fair Cut Diamonds offer little brilliance, as light easily exits through the bottom and sides of the diamond. Diamonds of a Fair Cut may be a satisfactory choice for smaller carats and those acting as side stones.

Diamond Colours According To The Diamond Colour Chart

The GIA diamond colour scale is the leading industry standard of diamond colour grading. Before this was the standard, other colour grading scales used A, B and C, so GIA started their scale at D to avoid confusion.

There are six categories on the GIA diamond chart, with colour grades that range from absolutely colourless to light in colour. Diamonds rated D are the most devoid of colour and very rare, whereas G colour diamonds and H colour diamonds are near colourless, and since they’re priced lower they are excellent value diamonds. The more you move down the colour chart, the lower the colour grade is, and the more noticeable the light yellow hue becomes.

D: Absolutely colourless. The most rare and valuable. Less than 1% of diamonds mined worldwide are graded as colour D.

E – F: Also considered colourless, even though it is a minimal trace of colour that can only be detected by an expert gemmologist. Less rare than D, and more valuable than G – H.

G – H: Near colourless. To the naked eye these diamonds appear clear and colourless, although they also contain minute traces of colour. Less rare than E –F, but more valuable than I – J.

I – J: Near colourless with a faint tint of yellow. Less rare than G – H, but more valuable than K – L.

K - L: A faint yellow tint that is visible to the eye. Less rare than I – J, but slightly more valuable than M – N.

M – Z: A very light yellow tint, easily identified by the eye. Least valuable of the diamond colour grade.

Diamond Colour Buying Tips

If you're looking to buy fine diamond jewellery such as an engagement ring, it's important to understand how diamond colour affects price. Here are a few buying tips and things to know about diamond colour.

DIAMOND COLOUR IS THE SECOND MOST IMPORTANT FACTOR

When it comes to diamonds, less colour means higher quality. While brilliance is the first thing you notice about a diamond, colour is the second. The higher the colour grade, the less colour there is, and the more expensive it will be.

NEAR COLOURLESS DIAMONDS ARE THE BEST VALUE

For the best value, choose G-J diamond colour grades in the Near Colourless category. With these diamonds, the naked eye can’t discern any colour. The visible difference between diamonds of one colour grade (G-H or I-J) is so minor it's difficult to detect with the unaided eye, but the cost savings can be significant. Keep this in mind when choosing your diamond colour grade.

In general, to avoid a pale yellow colour, choose a diamond grade H or higher. For the purist, look for a D to F grade colourless diamond, which will have no discernible colour under magnification.

DIAMOND SHAPE, SIZE AND RING METALS MATTER

Diamond shape, size and your ring’s metal setting can visually impact diamond colour.


Ring Setting — Pairing diamonds with similar toned metals can neutralize colour in the diamond. Consider setting higher colour grade diamonds like Near Colourless diamonds (G-J) in yellow gold and Colourless diamonds (D-F) in white gold or platinum. A gold setting may show through a colourless diamond

Diamond Shape —Some diamond shapes may show or mask colour to varying degrees. For example, brilliant-cut shapes such as round and princess reflect more light, which means more colour is masked. Step-cut diamonds (emerald and Asscher cuts) may show more colour because they are cut with fewer facets, resulting in bigger "windows" through which to see the colour.

Fancy shaped diamonds, like pear and marquise may also show slightly more concentrated colour at their points.

Diamond Size — Colour is easier to see in larger diamonds. If you want a diamond above 1 carat, choose a G or H coloured diamond. I-J colour diamonds are best when just under a carat.

Clarity refers to how clean or clear the diamond is with respect to natural microscopic characteristics that were trapped within or on the diamond while it was forming. Internal characteristics are known as inclusions, and characteristics on the surface of the gem are known as blemishes. Inclusions may be crystals of a foreign material or structural imperfections such as tiny cracks, known as feathers, which can appear whitish or cloudy

Often times the inclusions are microscopic diamonds that were absorbed by the larger crystal before the diamond was carried to the surface of the Earth. The quantity, size, color, location, orientation, and visibility of inclusions all affect the final clarity grade of a diamond. Diamonds with no or few inclusions are considered particularly rare and highly valued

Because diamonds formed deep within the earth, under extreme heat and pressure, they often contain unique birthmarks, either internal (inclusions) or external (blemishes).

Diamond clarity refers to the absence of these inclusions and blemishes. Diamonds without these birthmarks are rare, and rarity affects a diamond’s value. Using the GIA International Diamond Grading System™, diamonds are assigned a clarity grade that ranges from flawless (FL) to diamonds with obvious inclusions (I3).

Every diamond is unique. None is absolutely perfect under 10× magnification, though some come close. Known as Flawless diamonds, these are exceptionally rare. Most jewelers have never even seen one.

The GIA Clarity Scale contains 11 grades, with most diamonds falling into the VS (very slightly included) or SI (slightly included) categories. In determining a clarity grade, the GIA system considers the size, nature, position, color or relief, and quantity of clarity characteristics visible under 10× magnification.

● Flawless (FL) - No inclusions or blemishes are visible to a skilled grader using 10× magnification

● Internally Flawless (IF) - No inclusions and only blemishes are visible to a skilled grader using 10× magnification

● Very, Very Slightly Included (VVS1 and VVS2) - Inclusions are difficult for a skilled grader to see under 10× magnification

● Very Slightly Included (VS1 and VS2) - Inclusions are minor and range from difficult to somewhat easy for a skilled grader to see under 10x magnification

● Slightly Included (SI1 and SI2) - Inclusions are noticeable to a skilled grader under 10x magnification

● Included (I1, I2, and I3) - Inclusions are obvious under 10× magnification and may affect transparency and brilliance

DEFINITION OF CARAT

Carat (ct.) refers to the unique unit of weight measurement used exclusively to weigh gems and diamonds. Carat weight is often confused with visual size even though it is actually a measurement of weight. Depending on the shape and type of gemstone being weighed, the weight will visually show itself differently. For example, a 1.00 ct. round diamond will measure around 6.5mm, and a 1.00 ct. round sapphire will measure around 6.0mm. This is due to the varying density of different gemstones. Total carat weight (t.c.w.) is a phrase that represents the total weight of all diamonds or other gemstones in a piece of jewelry, when more than one gemstone is used. Diamond solitaire earrings, for example, are usually quoted in t.c.w., indicating the combined weight of the diamonds in both earrings.

IMPACT OF CARAT WEIGHT ON PRICE

Once cut, color, and clarity grade have been determined, the carat weight of a diamond can be easily established to fit within a budget. Larger diamonds are much more valuable because they are discovered in nature much less frequently than small ones. Diamond prices actually rise exponentially with carat weight rather than linearly. For example, a 1.00 ct. diamond of a given quality is always valued higher than two 0.50 ct. diamonds of the same quality. In fact, a general rule of thumb is that a diamond of double the weight costs around four times more. “Under-sizes” are diamonds that weigh just below a cutoff weight. While fewer exist, they may represent an enhanced value. They are more difficult to find as a diamond cutter will choose to sacrifice beauty in order to cut a diamond with a weight that reaches one of the cutoff weights, or “magic numbers” as they are known in the industry. The cutoff weights are 0.50 ct., 0.75 ct., 0.90 ct., 1.00 ct., 1.50 ct., and 2.00 ct.

Diamond Weight

Carat is a term that refers to the weight of a diamond. Prior to the twentieth century, diamonds were measured using carob seeds, which were small and uniform and served as a perfect counter weight to the diamond. The word "carob” is the origin of the word "carat" that we use today.

Diamond Size and Diamond Carat Weight

The size of a diamond is proportional to its carat weight. When rough diamonds are cut and polished into finished diamonds, up to 2/3 of the total carat weight may be lost. Since larger rough gems of high quality are found less frequently than smaller rough gems of high quality, a single two carat diamond will be more expensive than two one-carat diamonds of the same quality.

In the United States, the majority of diamonds used in jewelry and sold as loose diamonds are one carat or less in weight. The average engagement ring diamond sold in the U.S. is less than 1/2 carat in weight.

A diamond will increase in weight much faster than it increases in actual "face-up" diameter. For example, while an ideal cut one-carat diamond measures approximately 6.5mm in width, a diamond of twice its weight measures only 8.2mm wide—less than a 30% increase. The graphic to the left helps illustrate this point.

Which Carat Weight Is Right For You?

This question has no direct answer. It is a choice that depends on personal preference and budget. When looking at a diamond engagement ring, what is most visible is the size of the surface area on the top of the diamond. It is difficult to measure a diamond’s carat weight simply by looking at it. Although carat weight influences cost quite a bit, it is advisable to focus on diamond cut and diameter.

Diamonds come in many different shapes. Each diamond shape possesses its own unique qualities, so exploring and learning about the various shapes is worth your while. Flawless Fine Jewellery offers the highest quality certified diamonds to satisfy all tastes.

While every diamond is unique, all diamonds share certain structural features. A diamond’s anatomy, or its basic structure, determines its proportions, brilliance, dispersion and scintillation. Each part of the diamond has a specific name, and having a basic understanding of how each part contributes to the diamond as a whole will help you find your perfect diamond.

A diamond is comprised of the eight main components. They are Diameter, Table, Crown, Table Spread, Girdle, Pavilion, Depth, and Culet. Below is a brief description of each part of a diamond and its location.

  • Diameter: The width of a polished stone, measured from edge to edge.
  • Table: The largest polished facet located on the top of the diamond.
  • Crown: The top part of a diamond extending from the table to the girdle. The crown is made up of bezel facets (crown mains), star facets, upper girdle facets (upper halves), and a table facet.
  • Girdle: The very edge (widest edge) of the diamond where the crown and pavilion meet.
  • Pavilion: The bottom part of a diamond extending from the girdle down to the culet.
  • Depth: The total height of a diamond measured from the table to the culet.
  • Culet: The small or pointed facet at the very bottom of the diamond.

Before purchasing a diamond, make sure that you have a basic understanding of a diamond’s anatomy. This will allow you to truly appreciate diamonds and all their intricacies, communicate with experts about a particular diamond, and, most importantly, it will assist you in making a well-thought out decision about which diamond is best for you.

An ideal cut diamond is a round, brilliant, or princess cut diamond that is cut to ideal proportions and angles and has excellent polish and symmetry ratings. An ideal cut diamond reflects almost all the light that enters it, and is among the rarest cuts. The ideal cut diamond is used as benchmark for grading all other diamonds.

Ideal diamonds are perfectly proportioned to refract light, producing that fire and brilliance up through to the table and crown. There are at least six "ideal cuts" being used today but only three of them (including the one by Tolkowsky ) are the most common.

Fancy Coloured Diamonds

Exceptional diamond colour can be traced to the lattice of carbon atoms that form a diamond’s microscopic structure. Over billions of years, coloured diamonds were formed through exposure to heat, natural radiation or the saturation of natural elements. These incredibly rare processes result in beautiful tones and deep saturations of colour that evoke a deeply personal response in each of us.

Diamonds in the normal color range are colorless through light yellow and are described using the industry’s D-to-Z color-grading scale. Fancy color diamonds, on the other hand, are yellow and brown diamonds that exhibit color beyond the Z range, or diamonds that exhibit any other color face-up. These rare specimens come in every color of the spectrum, including, most importantly, blue, green, pink, and red.

Gem diamonds in the D-to-Z range usually decrease in value as the color becomes more obvious. Just the opposite happens with fancy color diamonds: Their value generally increases with the strength and purity of the color. Large, vivid fancy color diamonds are extremely rare and very valuable. However, many fancy diamond colors are muted rather than pure and strong.

Fancy Color Diamond Quality Factors

Orange and Yellow Diamonds

The remarkable hue of yellow and orange diamonds can be attributed to one element: nitrogen. While a diamond is forming, nitrogen atoms will arrange in such a way that that blue light is absorbed, thus producing a yellow color. A specific grouping of nitrogen atoms is also responsible for the shading of orange diamonds, but will absorb light in both the blue and yellow spectrums.

Brown, Red & Pink Diamonds

These diamonds owe their color to a combination of intense pressure and heat. While still buried deep within the earth, these factors cause distortions in the crystal lattice that absorb green light, thus reflecting a pink hue. Ultra-rare red diamonds, which are essentially just deeply colored pink diamonds, have the same cause of color.

Gray & Blue Diamonds

For the most part, blue diamonds get their color from boron. When this impurity is present, it bonds to carbon in the crystal structure, absorbing red, yellow and green areas of the color spectrum.

Green Diamonds

It's not until the last leg of their journey to the earth's surface that diamonds get their green color. Just as they are about to leave the uppermost layer of the crust, these stones absorbs naturally occurring radiation, which causes them to reflect a green hue by absorbing red and yellow light.

Violet and Purple Diamonds

So far, all scientists are certain of is that the cause of color for purple and violet diamonds is crystal distortion. However, it is believed that the presence of hydrogen may be partly responsible for their hue.

A diamond certificate verifies each diamond’s specifications, including its color grade, carat weight, clarity grade and cut grade. You should never buy a diamond without a diamond certificate. The most well-known grading laboratories are the Gemological Institute of America (GIA) and the American Gem Society (AGS) and the International Gemological Institute (IGI).

A diamond's cost depends upon objective characteristics, the 4C's: Color, Clarity, Cut and Carat. The relationship between these four characteristics determines the value of a diamond. Although it is commonly assumed that carat is the most important member of the 4C's, color, cut and clarity have a much greater impact on the appearance of a diamond.

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