Know your diamonds

Finding the perfect diamond has never been easier

From a gemologist's point of view, the cut of a diamond is what determines its brilliance.

A diamonds cut has no single defined standard. Rather it is a set of measurements which determine the relationship between its dimensions, finish and light performance. The diamond's width and depth determine how light travels inside.

The more successful a diamond cutter is in balancing these considerations, the more valuable the stone will be. Even a colorless and flawless stone can be significantly diminished by a poor cut, because it will lack visible brilliance.

Beginning with the Basics - Carat

The weight or size of a diamond is measured in carats (ct.).

A carat is 0.2 grams and there are 100 points (or 200 milligrams) per carat. With an accuracy of 1/100,000 ct, the IGI scales provide a highly precise diamond weight and this weight is specified on the Diamond Report to two decimal points. Carat weight refers only to the weight of the diamonds and not to the dimensions of a diamond.

1 carat = 100 cents / 0.200gms / 200 milligram

Diamonds come in a variety of colors, some of them highly prized (pinks, blues, even yellow). However in a white diamond, the presence of a yellow tint will lower the price of a diamond. The less body color in a white diamond, the more true color it will reflect, and thus the greater its value.

Diamonds are graded on a scale of D (colorless) through X (light color). All D-X diamonds are considered white, even though they contain varying degrees of color.


Using a jewelers eye glass or loop at 10 times magnification, a trained eye can detect identifying characteristics which affect a diamonds clarity.

The most common are internal flaws called inclusions. Some diamonds have external flaws, which are called blemishes.

The size and location of these characteristics determine how the diamond is graded on scale as: FL - Flawless, VVS - Very Very Small inclusions, VS - Very Small inclusions, SI - Small Inclusions.

Round Brilliant

Round Brilliant

The most common style of cutting both diamonds and colored stones.

The standard round brilliant consists of 57 facets; and a typical length-to-width ratio of : 1 to 1.

Princess Cut

Princess Cut

A relatively new shape, the princess cut generally has 70 to 76 facets.

The ideal princess cut diamond should be perfectly square. More rectangular ones will have a length-to-width ratio greater than 1.10.

Pear Cut

Pear Cut

The pear shape is a brilliant cut, which means it has exactly 58 facets.

The form is inspired by the crystallisation of a pure and perfect drop of water and is also referred to as a tear drop.

Oval Cut

Oval Cut

Longer than the round, this perfectly symmetrical shape has a larger surface area than a round diamond with similar weight.

Oval brilliants usually have 56 or 57 facets.

Marquise Cut

Marquise Cut

The marquise cut is an elongated shape with pointed ends. This shape stands on its own as a solitaire.

The ideal marquise-cut diamonds should have length-to-width ratios between 1.75 and 2.25.

Radiant Cut

Radiant Cut

This versatile design combines the brilliance of the round, the grace of the Emerald cut, and the panache of the Princess.

Square shaped Radiants, should have a length-to-width ratio between 1 and 1.05

Emerald Cut

Emerald Cut

The Emerald cut is rectangular with cut corners and includes broad and flat planes that resemble stair steps when viewed from above.

The crystal clear view which this shape has to offer may allow for inclusions and colour to be more pronounced.

Cushion Cut

Cushion Cut

The last century's oldest design (also known as 'pillow-cut' diamonds) is available either in a square or rectangular shape, and includes rounded corners and larger facets to increase its brilliance.

Diamonds have a tendency to develop a film build up of oils from lotions, powders, soaps, and natural skin oils which take away from their brilliance and sparkle. Chemicals in the air can slightly oxidize the mountings of precious jewellery depending on the karat grade used.

Diamonds should be cleaned so that the maximum amount of light can enter and return in a fiery brilliance.

A little time and effort will go a long way to ensuring that your diamonds stay perfect forever.

Points to Note:

Store jewellery carefully in its original packaging or in a jewellery box.

Avoid exposing jewellery to chemicals, perfumes, cosmetics or lotions as this could cause tarnish and discoloration.

Avoid wearing jewellery when using household cleansers.

Separate your jewellery, or wrap each piece individually in tissue or small plastic pouches to avoid scratches.

Cleaning your Diamonds

Soak your diamond jewellery in a warm solution of mild liquid detergent and water.

Use a soft brush if necessary to remove dirt. Soft is the key - don't use a brush with bristles that are stiff enough to scratch the metal setting.

Swish the jewellery around in the solution, gently scrub away any residue or dirt, especially around the prongs or setting where build-up is common. Then rinse it thoroughly in warm water. Close the drain first, or put the Jewellery in a strainer to keep from losing it.

If the diamond and setting needs extra help, you can also use a wooden toothpick to very carefully push dirt away from the diamond and setting.

Dry the diamond jewellery with a lint-free cloth.

Note: Never use toothpaste or other abrasives to clean precious metal or gemstones.