Diamonds have long been known as a girls best friend. Known as the hardest natural substance on earth, with outstanding brilliance and fire, they are the enduring symbol of love the world over. There is nothing quite like choosing your own diamond from a selection of loose diamonds sparkling in front of you. What ever your preference is, don’t be limited by what is on the shelf in regular shops, when you can choose exactly what you want from a wide range of options. The idea of the four C’s as a standard for measuring the quality of diamonds is now well known within the retail market place, but less well known are the many other industry factors that go into making a good diamond ideal or exceptional. While the internet has become a valuable tool for research and purchases, it is very important to be able to view a diamond before committing to a purchase as many of their subtleties are not shown on a grading report. Many people are surprised in the small differences from diamond to diamond, and how much it changes the price.


The Four C's

Carat : As a measure of weight a diamond is weighed in carat’s, each carat is divided into one hundred points so that a one carat diamond is displayed as 1.00ct .

This is an important factor in pricing a diamond, as diamonds with a weight of 1.00ct or greater cost a premium in the market place compared to a diamond say of 0.98ct , or ninety eight points as the trade calls it. A well cut 0.98ct can appear as large or even larger than some 1.00ct diamonds and will cost significantly less.

Some people will sacrifice cut grade or color to fit a larger diamond into their budget, while others will select a smaller diamond of better quality for the same budget. There is no right or wrong here as size is always a personal preference.

Color : Is the natural hue of the diamond, or tint as some would say. The best diamonds are completely colorless and are known by the color grading of D and command the greatest prices. Listed below are the color gradings by the GIA and what they mean to the general public.

Diamonds with more color in them without being a distinct fancy color will quite often appear dark as soon as your jewellery gets a little dirty. We recommend a minimum color grade of “H” or better for a clean white diamond.

Exceptional White +
Exceptional White
Rare White +
Rare White
I, J
Slightly Tinted White
K, L
Tinted White
M to Z
Tinted Color
Fancy Diamonds

Clarity : Most diamonds contain small marks of some kind that were created during the formation of the crystal, these marks are called inclusions and can effect the way the light reflects inside the diamond. In many cases it is not only the size and nature of the inclusions, but also there placement within the body of the diamond that can effect the price and quality of the gem. Clarity is still graded by human eye, and has a slight margin for interpretation by the grader.

Two diamonds may receive the same grade on their certificate because they have the same size and style of inclusion, but one will have the inclusion in the middle of the diamond, impacting on both its beauty and its value, while the other will have its inclusion out near the edge of the diamond, where it can only be seen by the most experienced diamond experts. In the trade this is what we call a good SI, because once it is set in a ring the inclusion can not be seen at all. Below is a description of what the clarity grades mean.

We feel that where ever possible a clarity grade of “VS2” or better is best if your budget allows it , but many “good SI” diamonds can be found if you look hard enough.

FL or IF
Flawless or Internally Flawless
Cannot be seen with a standard 10 times magnification
VVS1 or VVS2
Very Very Slight Inclusions
Can be seen with difficulty with 10 times magnification
VS1 or VS2
Very  Slight Inclusions
Can be seen with ten times magnification
SI1 or SI2
Slight Inclusions
Can be seen easily with ten times magnification
P1 or I1
Pique or Imperfect Grade 1
Can be seen without any magnification
P2, P3 or I2, I3
Pique or Imperfect Grade 2
and 3
Can be seen easily with the naked eye

Cut : Perhaps the most important of the four C’s, a diamonds cut can make a good stone brilliant and a great stone average. A well cut diamond will have exacting proportions to maximize its brilliance, fire and scintillation.

Diamonds that are cut too shallow will leak light out of the side and back of the stone and will appear flat and lifeless, although these diamonds are not as common in the trade today as they are under weight for there size.

Diamonds that are cut too deep will bounce light out of the bottom of the stone and will generally appear dark and grey looking, many jewelers combat this with special down-lights to make the diamonds appear as bright as possible. The best test is to hold the diamond under the desk or counter, or to shield it with your hand to see if it is still bright with minimum light, after all most of us don’t have jewellery shop lighting at home!

Perfectly cut, or Ideal cut diamonds will appear bright where ever they are, reflecting the fire and brilliance of what ever light is available.

Beyond The Four C’s :

As well as the four C’s, all reputable diamond grading reports also grade symmetry, polish and fluorescence as well as the cut.

Symmetry : While the cut describes the proportions of the diamond, the symmetry describes the balance of the faceting on the diamond, each facet in a perfect diamond being of exactly the same size and shape of its like minded opposite, and both the table and the culet of the diamond being perfectly centered.

Polish : Most diamonds appear to be as smooth as glass, but under magnification small surface marks such as pitting, abrasions, scratches and polish lines can be seen, these marks while seeming insignificant can play with the natural dispersion of light from the diamond.

These two factors are graded in a range from Ideal, Excellent, Very Good , Good , Average and Poor, some diamond grading laboratories refuse to grade diamonds that fall below a Good grading because of there poor light reflecting properties. When asking for a good quality round brilliant cut diamond, jewelers will often ask fora triple X, that is a diamond that has received a grade of excellent for its cut, polish and symmetry.

Fluorescence : Approximately 25% of GIA graded diamonds show some signs of natural fluorescence, this means that they will glow under an ultra violet light ( or when you go out to a club with the girls). In the jewelers shop the lighting systems can often hide the effects of fluorescence, and sometimes even make low colored diamonds appear brighter, but when good quality diamonds display medium to strong fluorescence they can appear to be slightly milky, hazy or oily on the surface when placed in natural sunlight.

This can appear on the grading report as Nil or None, Faint, Medium, Strong or Very Strong. The best diamonds will always receive a grade of Nil.

The Shapes

Diamonds are becoming available in an increasing variety of shapes these days, and while many can appear to be just as bright as the traditional round brilliant cut diamond it is important to note that the same exacting standards in cutting don’t apply to the fancy shaped diamonds. Below is a description of some of the more popular shapes today, and what to look out for in them.

Princess : These diamonds are square in shape and are perfectly suited to geometric designs and are perfect for channel setting in wedding bands. One should be careful to choose a diamond as close to square as possible as rectangular diamonds often throw off the balance of the design as well as sometimes appearing dark down the long side of the diamond.
Marquise, Pear and Oval : These diamonds are quite often used as the center stone for a three diamond ring. They usually display a dark bow tie, or windmill effect across the middle of the diamond because there length doesn’t allow the light to disperse through the diamond evenly. Exceptionally well cut diamonds can minimize this effect, but these diamonds are harder to find and are not very common in the marquise shape. As a solitaire they show a greater surface area for their weight than the traditional round brilliant cut.
Cushion : An old style of cut that is becoming increasingly popular today with the antique and art deco revival. Diamonds should be as square as possible to suit most designs and to give maximum light dispersion, but many beautiful rectangular diamonds are available if you look hard enough. One needs to be careful of heavy cut diamonds, this is becoming very common in this style of cutting. These diamonds
will appear smaller than a round diamond of a similar weight because of their square nature.
Radiant : Becoming ever more popular now, especially in the fancy colored diamond market, these diamonds have the square nature of the Princess cut but without the hard sharp corners. They lend themselves well to geometric designs as well as the three stone style of ring and many antique and art deco cluster styles.
They are available in both well cut square and rectangular shapes. One should look out for shallow cut stones, especially in the rectangular variety as these can appear to be glassy down the long sides or they display the bow tie effect common with long shaped diamonds. They are especially suited to fancy colored diamonds, as their cut tends to enhance the the depth of color present in the diamond.
Emerald : This is an older more traditional type of cut, and is more often found in colored gemstones ( hence the term “emerald” cut ). Rectangular in nature their length is generally 1.5 times their width, and can look quite good as a set of three, five or even seven graduated diamonds. One should stick to high colored stones ( D, E or F ) and a clarity of VS1 or better as these diamonds have a tendency to highlight inclusions within them and make them more obvious than they are.
Asscher : These are a modern square variation on the more traditional emerald cut, they can be a very bright white diamond, but will need regular cleaning to keep that maximum brilliance. Diamonds Should always be perfectly square ( within 0.1 of a millimeter or less ) because of there geometric nature and can sometimes show an obvious windmill effect. The heavy nature of this cut will mean that they will appear slightly smaller than a diamond of the same weight in a different cut.
Baguette : These are the perfectly rectangular version of an emerald cut and are usually found in smaller sizes as side stones, although now they are becoming available in sizes upwards of one carat as center pieces of there own and are increasingly popular in mens rings. They are also available as a tapered diamond in smaller sizes, which are ideally suited as side diamonds in three stone rings. The advice is the same as for emerald cut diamonds.
Heart : Geometrically speaking , they should measure the same in length as they do in width to give maximum fire and dispersion, although they rarely do. They can make a beautiful center piece, especially in pendants and go very well as side stones for marquise and oval three stone rings, although matched pairs can be hard to find. Look out for heavy cut stones, or those with an uneven or lumpy silhouette.
Trilliant : Triangular in nature, as there name would suggest, they are more often than not used as side stones for three diamond rings. They can be placed against virtually any shape of center diamond with very good effect. They should generally be of a high color because of the shallow nature of their cut, and can sometimes display the bow tie effect to the middle of their three sides when cut poorly.

Diamonds also come in a myriad of other shapes these days, such as the traditional Tapered Baguette, Shield, Kite, Bullet, Crescent, Half Moon, Trapezoid and others, including some cut in the shape of initials.


Fancy colored diamonds have long been highly sought after as the most rare of gems, from King Louis XIV’s Blue Diamond of the Crown ( it has since been recut into the Hope Diamond ) , through the Crown Jewels and the 128.54 fancy yellow Tiffany Diamond, to the vivid pink diamonds of the Argyle Mines, the colored diamond is available in virtually any shade and color that takes your fancy. Finding the money for it might be another problem altogether, as these diamonds are becoming much harder to find today, and demand in some colors is outstripping supply.

Colored diamonds are graded according to their properties of hue (spectral color), tone (lightness or darkness) and saturation ( intensity). In all cases, regardless of the hue (or color), the greater and more even the saturation, the higher the value.

The pink diamonds of the Argyle Mines are quite possibly the rarest and most beautiful gems in the world, although more affordable options are becoming available today with the champagne/pinks that are now coming on the market.

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150 Springfield Rd, Blackburn, Victoria 3010, Australia