Your cart is empty

The 5Cs of Diamond Grading - What you need to know.

A Guide to Diamond Cut


Although diamonds have been in existence for billions of years, it is only in recent history that humans discovered a way to intensify a rough diamond’s beauty: by cutting various facets into it, and then polishing each of those facets to increase its brilliance. shop loose diamonds


Diamonds are known for their brilliant sparkle and the intensity with which they reflect light. A diamond’s cut is one of the most important (and visual) aspects to consider when grading a diamond, as it directly determines the diamond’s fire, brilliance and scintillation. Often confused with a diamond’s shape (round, princess, emerald, cushion, etc.); the cut of a diamond refers to how well the diamond has been cut and polished, regardless of its final shape.

Each Shimansky Diamond is personally inspected to deliver to you the best brilliance and value you deserve in any size, shape color and clarity.

Contact us for a free quotation


Diagram of the ideal cut diamond


The Correct Proportions Are Needed For The Ideal Cut Diamond


What differentiates ‘cut’ from the other grading criteria, is that it is not entirely determined by nature. A diamond is cut and polished at the hands of a master craftsman who ensures that each facet is polished to perfect proportion and symmetry. The more precise and scientifically calculated the cut, the more beautiful and captivating the diamond becomes. It takes a master diamond cutter hours of analysis before the cut, that will yield the most beautiful and valuable diamond, is determined. The cutting and polishing process takes several days and is vitally important – even if a diamond is highly graded in all of the other 4Cs, a bad cut or polish will leave it looking dull and underwhelming.


“The joy of a perfectly cut diamond is not just in its beauty, but in the way it makes you feel,” says Yair Shimansky, founder and CEO of Shimansky. Each Diamond is personally inspected to deliver you the best Brilliance and Sparkle you deserve.


When choosing a diamond, have a look at the diamond certificate, which will state how the cut has been graded. A round brilliant cut diamond (the most popular diamond cut) is graded in the form of Excellent, Very Good, Good, Fair or Poor. A diamond that is cut too shallow will “leak” light out the bottom and if the cut is too deep, light will escape from the sides. In a well cut diamond, with the correct proportions and symmetry, the light that enters the diamond is returned out of the table and crown of the diamond, giving it the best sparkle.

We will help you in making scene from the combination of all the different parameters a diamond have to deliver the best suitable diamond option to suite your need.

Every Diamond Cut & Shape from Round Brilliant, Cushion Cut, Pear Shape, Emerald Cut, Oval Cut and more require a professional examination taking into consideration all the factors that make the diamond performance and value.

Shimansky is your trusted Diamond Expert with over 25 years of hands on (and a loup) experience and expertise.



GIA report showing diamond cut grading

A GIA Diamond Grading Report


My Girl Diamond Cut Patented By Shimansky

Shimansky is renowned for several signature diamond cuts, such as the My Girl Diamond Cut, Known for its perfect balance of Brilliance, Fire and Scintillation, designed and patented by Yair Shimansky, Also the Brilliant10 Diamond a 77 Faceted Round Diamond known for its Perfect Brilliance for the ones who seek perfections in diamonds and are happy to pay a slight premium for the best diamond cut in the world. . The Shimansky My Girl diamond is the world’s first Square Shape  diamond with a Diamond-shaped table and a Virtual Facet offering the perfect balance of fire, brilliance and scintillation, with as much as half the rough stone is sacrificed to create the perfect cut Diamond. Read more here.


The Brilliant 10 diamond was designed and developed by Yair Shimansky after extensive research in light behavior and optics. He says, “the Brilliant 10 diamond displays up to 20% more brilliance than a normal diamond and is up to two shades whiter in color than its actual color.” The Brilliant 10 has been tested as the most brilliant cut diamond in the world, with unique characteristics that cannot be found in any other diamond cut. Read more here.

Due to a special Rough Diamond Shape only few diamonds are selected to be cut and polished into the Brilliant10 Cut Diamonds -We can cut specially for you if you can afford a  2-3 month waiting time  for the best Diamond in the world.



super ideal diamond cut diamond showing hearts and arrows formation

View Through 10x Magnification In The Hearts &Amp; Arrows Diamond


In addition to the patented diamond cuts Shimansky has on offer, the Eight Hearts diamond is a true Hearts and Arrows diamond. The diamond cut is perfectly proportioned to reveal eight hearts when viewed through the bottom and eight arrows when viewed through the top using the Ideal Scope. The perfect alignment and proportioning of the eight hearts and eight arrows is visual proof that the diamond has been cut and polished to perfection. Only one in a million diamonds can be called a true Hearts and Arrows.

Each certified diamond’s cut grade is recorded on its accompanying diamond certificate from the GIA (Gemological Institute of America), EGL (European Gemological Institute) or SGL (Scientific Gemological Laboratory), proving its authenticity. Remember to ask the store consultant for the diamond certificate when viewing a diamond.

The best 57 Facet Diamond Cut you can get.



Diamond Color Guide


Diamonds come in different shades of color and can range from colorless to varying shades of yellow. Even though most diamonds appear colorless to an untrained eye, many have slight tones of yellow or brown that affect its value. The closer a diamond is to colorless, the more valuable it is.


White or colorless diamonds are graded on a color scale from D (colorless) to Z (heavily tinted yellow). A universally-accepted and standardized color grading system, it has been accepted since the 1950s. This grading is done in a special, controlled environment because the difference between each shade is very subtle and often not noticeable to the untrained eye.


color grading system of a diamond

How Diamonds Are Graded In Accordance To Their Colour


In addition to the D – Z color scale, natural fancy color diamonds such as deep yellows, pinks, greens and blues lie outside the white diamond color range and are extremely rare and valuable. These natural fancy color diamonds are graded according to the intensity of their color. The more intense and vibrant their shade, the higher their value. It’s important to note that a diamond with a yellow tint and a natural fancy color yellow diamond are not the same. A white diamond with a yellow tint is subtler in color, while a fancy color yellow diamond comes in various shades of rich and vibrant yellow.


Each certified diamond’s color grade is recorded on its accompanying certificate from the GIA, EGL or SGL. Remember to ask the store consultant for the diamond certificate when viewing a diamond.

Shimansky Fancy Yellow Diamonds are origin from the West Coast of Africa and the Orange river with a beautiful Shades of  Yellows all GIA graded and certified.


Shimansky fancy color diamond rings

Naturally Fancy Colored Diamond Rings In Blue, Pink And Yellow


D: Absolutely colorless. The most rare and valuable. Less than 1% of diamonds mined worldwide are graded as color D. Also known ad the Blue White Diamond


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

Popular with Platinum Jewelry due to the Pure White Color


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


A Popular choice for Engagement ring in White Gold available in any carat weight and diamond Shape and Cut.


I – J: Near colorless 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 color grade.

GIA certificate showing diamond color grading


A GIA Diamond Grading Report Depicting Color


Fluorescence in Diamonds


Fluorescence in a natural phenomenon affecting almost a third of all gem-quality diamonds. Often misunderstood, fluorescence it is just something that happens, which means that a diamond emits a soft-colored glow when it is exposed to ultraviolet (UV) light. We are exposed to UV light every day, through sunlight, and through the light produced by fluorescent light bulbs. The characteristic of fluorescence is caused by the presence of Nitrogen and is a natural phenomenon – like color, it is completely natural within the gem and you can’t create it.


When a diamond has fluorescence, there are two factors that should be considered:


Color: Blue is the most common color of fluorescence (95%), with yellow being the second most common color. Diamonds with blue fluorescence tend to appear whiter than their grading suggests. This is a good thing for the buyer, as the diamond will have the appearance of a diamond that is worth much more. However, diamonds with yellow fluorescence appear more yellow in color when exposed to UV light, which is seen as a negative aspect, as diamonds with a yellow tint are worth less than diamonds that are near colorless. It could thus mean that a diamond with yellow fluorescence looks like a diamond that has a low color grading, even though its true body color is actually of a high grade.


diamonds fluorescence appearance when exposed to UV light



Strength: The strength of fluorescence varies from none, faint and medium to strong and very strong. Though some diamonds have very strong fluorescence and appear dull or cloudy even in regular lighting conditions, the majority of diamonds do not have a widely notable fluorescent appearance when looked at with an untrained eye.


Fluorescence affects the value of a diamond depending on its color and strength. If there is a strong yellow fluorescence present, it may decrease the value of the diamond, while the presence of blue fluorescence may increase the value of a diamond that does not have a high color grading (and thus has a yellowish tint). Diamonds certified by the GIA or EGL clearly state on their Certificates of Authenticity whether there is a presence of fluorescence. If the diamond does not have fluorescence, it will be marked as “none,” and if fluorescence is present, it will be noted as either “faint,” “medium,” “strong” or “very strong.”


Because fluorescence is a natural phenomenon, it cannot be judged in isolation. Each diamond is unique, and fluorescence thus affects it in a unique way. When shopping for a diamond, always be sure to look at its unique characteristics and qualities and make sure you understand the grading on its certificate.


Diamond Clarity Totorial


Diamonds were formed billions of years ago, under conditions of extreme pressure and temperature. Almost all diamonds display tiny ‘birthmarks’, called inclusions, which occurred naturally when the diamond was formed deep within the earth. They are nature’s fingerprint and give each diamond its unique character.


clarity in diamonds



Clarity refers to the presence of these natural inclusions or imperfections found in a diamond. The clarity of a diamond is determined by the size, number and nature of the inclusions present in the stone. Inclusions refer to imperfections that occur naturally inside the diamond itself – they are not man-made, and are believed to have formed during the crystallization process of the gem. Inclusions may take shape in the form of tiny white points, dark dots or feathery cracks.


Blemishes refer to imperfections that occur on the surface of the diamond as a result of the cutting and polishing process. These can come about when a diamond cutter or polisher is not experienced, or has not yet mastered the craft.


using a loupe to inspect a diamond



    • Most inclusions are not visible to the naked eye, so diamonds are examined under a 10x magnifying Diamond Loupe to determine their clarity. The closer a diamond is to flawless with no inclusions visible under a jeweler's loupe, the more rare it is and the greater its value. Flawless diamonds are so rare, that many jewelers spend a lifetime in the diamond industry without ever finding a completely flawless diamond.


  • The position of the inclusion can also have an impact on the gem’s value. An inclusion situated directly below the diamond’s table, for example, will have a larger impact on the diamond’s clarity than an inclusion of the same size situated off the side of the diamond. A diamond cutter will make every effort to cut the stone in such a way that the inclusion is not visible through the table of the diamond.


A diamond’s clarity is graded from F (Flawless) – the rarest of the rare – to I (Included). Clarity is divided into different categories (Flawless, Internally Flawless, two categories of Very, Very Slightly Included, two categories of Very Slightly Included, two categories of Slightly Included, and three categories of Included).


When choosing a diamond, you should select a clarity grade in which the inclusions are not visible to the naked eye (i.e. a clarity grade of SI and up). A diamond’s clarity is unique and acts as a fingerprint.


A diamond containing several or large inclusions has less brilliance than a diamond containing less or smaller inclusions, as flaws in a diamond interfere with the path of light as it travels into, and then out of, the stone.


Shimansky carries Flawless (FL / IF) to Slightly included (SI) diamonds.


clarity grading in a diamond from flawless to included



Though inclusions have a negative effect on the value of diamonds, there are two positive aspects of their existence:


  • Inclusions give diamonds their unique characteristics. Diamonds are produced by nature, and like all things in nature, imperfections are common, and sometimes even welcomed. Just like each snowflake is unique, there are no two diamonds on Earth that are exactly the same. Inclusions contribute to a diamond’s individuality, and are often helpful in identifying a gem. They also provide scientists and gemologists with valuable information about how a diamond was formed.


  • Inclusions can also help a gemologist to separate a real diamond from an imitation. It can be difficult to separate a flawless diamond from an imitation diamond, but when natural inclusions are present, it indicates the authenticity of the stone’s origin.

   We inspect every diamond to deliver you the best option withing the Clarity         Range you select based on your needs.

GIA report showing the clarity grading of a diamond



Diamond Carat Weight


Carat is the standard unit of weight used for gemstones. 1 carat = 0.2 grams, or 200 milligrams. The higher the carat, the more rare and more valuable the diamond. Just as currency is divided into smaller units, a carat is divided into 100 points. For example, half of a carat will weigh 0.50 carat (ct). A quarter of a carat will weigh 0.25 carats (ct), and so on.


Does size matter? Large diamonds are rarely found in nature so they are more valuable than smaller diamonds of the same color and clarity. This means that the price of a diamond will increase exponentially as the carat size of the diamond increases. Diamonds of one carat or larger are so rare that they represent only 1% of all the diamonds mined worldwide. Many of the world’s largest diamonds were found in South Africa. “South Africa has produced some of the world’s largest, most valuable and memorable diamonds and today maintains its position as a top diamond producer,” says Yair Shimansky, Founder and CEO.



However, big does not necessarily equal better. While the size of a diamond has the greatest influence on the price, the cut, color and clarity will affect a diamond’s brilliance and beauty. A diamond with a large carat weight, but with a low color, cut and clarity grading could, for example, be more less valuable than a diamond of lower carat weight, but with exceptional color and clarity.


Similarly, two diamonds of equal carat weight could vary significantly in price if one were to have a higher cut, clarity or color grading.



1 carat equals to 0.2 grams



Though the carat weight of a diamond gives an indication of its size, weight and size should not be confused with one another: The size of a diamond is also dependent on its cut and shape. It is quite possible for two diamonds of the same carat weight to appear to be different sizes. Each individual diamond’s proportions (such as the table and depth percentages) must be taken into account to determine its size. A shallow diamond with a wide table may appear larger than a diamond with a deeper cut, and a narrower table, yet they may have an equal carat weight. An elongated shape such as a Marquise tends to maximize carat weight, as it makes the stone appear larger than that of a traditional round shape of a diamond of equal weight.


The term carat originates from the seed of the carob tree. In ancient times, before scales and units of mass were invented, diamond traders compared the weight of a diamond to the seeds of the carob tree. Each carob seed had a uniform weight, equal to 0.20 grams or 200 milligrams and hence determined the weight of the diamond. The carat metric was officially adopted by the United States in 1913, with other nations soon following suit. Today, the carat is a universal metric measure, with all nations adhering to the exact same measurement. That means that when you purchase a diamond, it will have the same carat weight everywhere in the world.


Shimansky offers a wide variety of diamond sizes to meet all your jewelry needs: From larger diamonds weighing over a carat, to the smallest of diamonds found in a micro setting, and everything in between. Shimansky diamonds are cut to maximize their beauty and their brilliance – not to emphasize their size. That means that all Shimansky diamonds, regardless of their size, are cut and polished with the same passion and attention to detail. Whatever the size of the diamond that captures your heart, you can be sure that it was cut and polished with the utmost of care, and that it displays the maximum amount of fire, brilliance and scintillation.



When selecting a diamond size for an engagement ring, it is important to take the wearer’s ring finger into consideration. A long, slender ring finger will make a diamond appear larger, while a shorter finger could make it appear smaller. Similarly, the diamond’s setting can also have an impact on the appearance of the diamond’s size. A delicate setting tends to enhance a diamond’s size and prominence, while a bulkier setting could make the diamond appear smaller. Whilst it is important to take these factors into consideration when selecting a diamond size, one must remember that they only have an effect on the appearance of the size of the diamond; they do not alter the carat weight in any way.


The carat weight of a certified diamond is recorded on its accompanying certificate from the GIA, EGL or SGL (proving its authenticity). Remember to ask the store assistant for the diamond certificate when viewing a diamond.


carat weight recorded on a GIA certificate



Confidence In Buying Diamonds


Equally important to the cut, color, clarity and carat weight of a diamond is the 5th C – Confidence.


diamond and tweezers and loupe



Purchasing a diamond is a special occasion, one that usually involves a lot of deliberation and planning on the buyer’s side. Confidence in knowing that you are buying your diamond through a reputable jeweler and that the diamond was sourced ethically is absolutely vital when selecting your diamond or diamond jeweler creation.


At the heart of every diamond jewelry creation, is a story. Whether it is the story of how your partner created the perfect engagement, or the beautiful memory of a golden wedding anniversary, a diamond celebrates the special moments that we wish could last forever. When selecting your diamond, it is important to choose a reputable jeweler that recognizes the magnitude of your occasion, and the importance of finding the one (or more) that captures your heart.


Shimansky is one of the only jewellers in the world to source rough diamonds direct from the South African mines - and to cut and polish their diamonds in-house. You can trust that every step, from the sourcing of rough diamonds from ethically-bound mines to the cutting and polishing process is handled by the best in the industry to ensure that you own a sustainable diamond – a Shimansky diamond. The Shimansky diamond cutting and polishing workshop is located in the Clock Tower at the V&A Waterfront, alongside the Shimansky diamond showroom, and Cape Town’s only dedicated diamond museum, The Cape Town Diamond Museum.


“Cutting and polishing our diamonds in-house creates value every step of the way,” says Shimansky founder and CEO, Yair Shimansky. Because the diamond stays within the Shimansky family from its rough state, all the way to its final setting in a jewelry creation, it is possible to control the quality of its cut and polish, as well as the integrity in which the work is done.


Shimansky diamonds are graded by international and independent grading laboratories such as the Gemological Institute of America (GIA) and the European Gemological Laboratories (EGL). Such certificates serve as proof of the diamond’s grading, and also contains vital information such as the proportions of the diamond, details of its inclusions, and notes on its polish, symmetry and fluorescence.


When purchasing a diamond, it is important to select one that has been cut and polished to maximize its potential in terms of brilliance. Though color, clarity and carat weight is determined by nature, it is the diamond cutter who is responsible for cutting the diamond in such a way that it yields a high grading for its cut. Any blemishes (nicks and scratches on the surface of the diamond) accidentally caused by the diamond cutter will impact the diamond’s value greatly. At Shimansky, a team of world-class experts, with a wealth of experience and skill, work with the utmost concentration and dedication to ensure that each and every Shimansky diamond is cut to realize its full potential. The continuous pursuit of perfection is the driver that sets the standard for all Shimansky jewelry creations.


shimansky diamond engagement ring



At Shimansky, we understand the importance of celebrating the special moments in people’s lives. The customer is buying more than just a diamond – they are buying a moment of beauty that will stay with them for the rest of their lives,” Shimansky explains. When embarking on the journey of finding the diamond that is perfect for you or your loved one, you’ll be guided by a team of passionate and dedicated Shimansky professionals. Just like every diamond is unique, each person has their own unique taste and preferences. Shimansky offers a wide variety of diamond jewelry creations: From patented original designs such as the iconic Millennium Diamond Ring, to classic Solitaire Diamond Engagement Rings, there is a style and cut to capture every heart.


The beauty of a Shimansky original is only truly realized when it is worn by the one it was meant for,” says Yair Shimansky. When embarking on your diamond-buying journey, always select a jeweler who has your best interest at heart and who will guide you in finding exactly what you are looking for.


shimansky diamond engagement ring



Beyond the 5Cs – What You Didn’t Know You Needed to Know


Each diamond is a unique gift from nature, rare and miraculous in its formation. With every diamond purchase, the 5Cs should be carefully considered, as it is incredibly important to select a diamond that speaks to your taste, and captures the essence of the moment in which it will be presented. It is important to know the characteristics of a diamond, not only to make an informed purchasing decision, but also to ensure that you get the best possible value. However, there are various diamond attributes that do not fall within the cut, color, clarity or carat weight spectrum. These attributes go beyond the 5Cs, and are very often intangible characteristics. When selecting a diamond, it is important to consider the following aspects:


diamond reflecting fire and brilliance



Diamonds Character:


Each diamond is selected individually for its unique character. While two diamonds may have the same characteristics in color and clarity; their character will differ. Even if two diamonds were to have the exact same grading for the 4Cs, they will never be identical, and a person may, for any reason, think the one is more beautiful than the other. It is almost certain that one diamond will speak to you more than another. A diamond’s character cannot always be explained and is often likened to chemistry – a person may be drawn to it without having tangible reasons why. It is something that speaks to the heart, and is often felt at the first glance.


symmetry and light reflection in a diamond





Presence is a combination of the diamond’s perfection in cut, symmetry and polish. A diamond’s presence affects the overall appearance of a diamond and the manner in which it reflects light. When a diamond cutter achieves perfect mathematical symmetry and completes the cut and polish with precision, the diamond’s fire, brilliance and scintillation will be truly realized and maximized.


Fire, Brilliance and Scintillation in Diamonds:


  • Fire refers to flashes of light seen within a diamond, resulting from light dispersion. Diamonds that are cut to very good or excellent proportions will display a higher degree of fire.
  • Brilliance describes the amount of white light reflected from the facets of a diamond. Brilliance is a combination of lustre, light reflection, color dispersion and scintillation.
  • Scintillation is the amount of reflected light from a diamond visible when it moves. This is also known as sparkle.


polished diamond



Personal Preference when choosing a diamond:


Like with any other purchase made in life, personal preferences will always play an important role. A diamond could meet all the requirements needed to have a high grading, and meet a high price, but if a person does not like the cut, shape, or color, or if they just don’t feel a connection with the diamond, it doesn’t matter how great it is on paper, it will not be the right purchase for that person. According to Shimansky’s founder, Yair Shimansky, a diamond should “speak to your heart.” A diamond should capture a special moment in your life, or remind you of a special memory.


Shimansky realizes the importance of finding the perfect diamond, and takes great pride in making the journey to this discovery insightful and enjoyable. A diamond should “celebrate brilliant moments and create everlasting memories,” says Yair Shimansky. When viewing the various diamond options available at a Shimansky store, you will be guided in finding the perfect diamond suited to your unique preferences. After all, a diamond is as unique as you are.

Remember - Shimansky is your partner in selecting the best Diamond to suite your needs at any budget, ethically mined and sourced directly to you without any middle man at the fairest price.