Grading Terminology

GIA’s grading terminology uses a combination of fancy grades and colour descriptions to identify a coloured diamond’s characteristic colour. A fancy grade represents the combined effect of tone and saturation on the colour of a diamond.

All Ladylux fancy colour diamonds are accompanied by a GIA colour diamond report. All Ladylux fancy colour diamonds are of natural colour. This means that their original nature, when mined from the earths depths, were of this colour hue as seen in its final state. There is no treatment to the diamond to obtain the colour that is seen within the diamond.

GIA has established a colour grade scale that encompasses the hue, tone and saturation of colour as seen by experienced gemmologist. At GIA several gemmologists must be in agreement for the unknown diamond to be assigned a final fancy colour grade. All colour diamonds are tested for all known treatments that can enhance or impart colour to a diamond.

HUE The Predominant Colour

The appearance of a diamond to be classified as red, green, blue, violet, or anything in between. Colour description of a diamond can be a combination of two or more colours. When reading the colour description of a diamond on the GIA report the final colour hue is the dominant colour and any other colour description before it is a modifier. There are eight dominant colour hues that are used in the GIA grading system and include: Red, Orange, Yellow, Green, Blue, Violet, and Purple. The red is further defined by using Pink as the dominant colour completing the scale to eight colours. Brown and grey are not considered in the same context as the dominant eight and are often used as modifiers for specific hues, but can stand alone with a fancy designation.

Tone

Lightness or Darkness. The Tone of colour grading refers to the lightness or darkness of the hue, or primary colour of the diamond.

Saturation

Saturation refers to the dominance of hue in the colour, and Intensity of it. Saturation is the measure of how strong and intense the primary colour of the diamond actually is, such as light, deep, intense or vivid. A fully saturated colour is the truest version of that colour. Primary colours (red, yellow, and blue) are "true", so they are also fully saturated. There are six categories in the GIA scale that equate to colour saturation.

Blue diamonds

Blue diamonds are formed by the concentration of boron in the bonding of atoms. As the amount of boron in a diamond increases so too does the strength of blue. Blue diamonds are almost always type II b, do not contain fluorescence and generally have few imperfections.

Argyle produces another form of blue diamonds of the type Ia type which are sometimes classified as violet by the GIA. These stones share qualities with their argyle pink cousins in that they are generally included and have fluorescence. Their colour is caused by the element impurity hydrogen present in their covalent bonding.

GIA grades blue diamonds in terms of tone and saturation. As tone and saturation increase rarity goes up as well as value. Starting from low tone and saturation and increasing GIA grades blue diamonds as light, fancy light, fancy, fancy intense/ fancy deep, and fancy vivid. All categories are very rare and small or large sizes.

MODIFIERS

Blue diamonds are modified by a violet, green, or grey. When reading a GIA certificate of a multi hue colour stone the last hue describes the dominant colour of the diamond. In other words a Fancy Grey Blue diamond shows more blue colour than a Fancy Blue Grey.

Grey exists when the Saturation of a diamond is not strong enough to mask the tone and as more grey is visible the less valuable the diamond generally is. Exceptions do exist however, demonstrated by the Wittelsbach and the Hope diamond, both are classified as having grey in their colour but are considered to be two of the most valuable diamonds ever mined.

Green can also be a modifier of blue diamonds. Green is present when a diamond has both boron in its atomic structure and has been near radiation for a period of its formation. Green as a modifier usually decreases the value of a diamond but not as significant as grey does. Once a stone is close to pure green however the value starts to increase once again.

Violet can also be a modifier of blue diamonds. Violet Blue diamonds are so rare however that the total amount of stones can be counted on ones fingers.

Pink diamonds

Pink diamonds are different from other fancy colours in that they do not get their colour from any trace element such as yellow and blue diamonds do. Instead, after their formation, these stones are subjected to very high temperature and non isotropic stress which deforms the crystal lattice and displaces some of the carbon atoms from their regular positions. It is accepted today that these structural defects are the cause of a diamonds pink hue.

In Argyle Pink Diamonds these defects are very obvious and can be seen as "graining lines" with the help of a microscope and in some cases even apparent to the naked eye.

Like other colours GIA grades pink in terms of tone hue and saturation. As tone and saturation increase rarity goes up as well as value. Starting from low tone and saturation and increasing GIA grades pink diamonds as light, fancy light, fancy, fancy intense/ fancy deep, and fancy vivid. Pink diamonds are unique in that when a stone falls into the rare category of extremely high tone and saturation GIA uses the term "fancy RED" to classify it.

MODIFIERS

Modifiers also exist in pink diamonds. These include brown, orange, and purple. A brown modifier exists when the saturation of the diamonds is not strong enough to overpower the tone. As the brown in a pink diamond becomes more apparent the value of the diamonds is significantly reduced.

Orange as a modifier is present when either the hue of the diamonds starts to lean towards orange or when the tone is starting to overpower the pink. Some orange -pink diamonds are very beautiful but because their colour is associated with brown the orange modifier also devalues pink diamonds.

Purple is the one modifier that does not significantly devalue a pink diamond. Argyle even adds a premium to the price for stones with noticeable purple hue. The colour in purple-pink diamonds is caused by the grain lines displaying a different wave length in the colour spectrum.

Yellow diamonds

Behind brown diamonds are the most abundant of the fancy coloured diamonds. Achieving their colour from the concentration of nitrogen in the atomic structure these stones can achieve extremely high degrees of saturation.

GIA awards the highest grades to diamonds with both high saturation and a low amount of tone. The term "canary" has been adopted by the trade as well as the public to describe a yellow diamond and "Zimey" to describe the strongest of vivid yellows.

MODIFIERS

Yellow can be modified by the hues brown, orange and green. Brown is considered a great deterrent to the value of the stone with orange and green sometimes considered an advantage. Still strait yellows especially in strong saturation grades are rare and valued highly.

Yellow differs from other colours in that their exists a wide range of colour in the highest GIA grade, vivid yellow.

Green diamonds

Green diamonds are one of the most difficult diamonds to value and understand on the coloured diamond market. The reason for this is the way in which green diamonds are formed. Caused by exposure to natural irradiation during the diamonds formation, the colour of green diamonds can either be throughout the stone or just present on the surface.

What expert cutters are now doing is leaving "skin" or surface radiation staining on the stone to give the appearance that the stone is greener than it is. Because the GIA grades colour on face up appearance and because the skin is natural there is little indication how the stone appears green.

Generally how one can tell is to view the diamond loose and see how much of the stone is in its rough form, the less the better. Green diamonds with the same GIA grades can be fractions of one another in value because of green "skin". This should not deter a collector from purchasing a skin stone however because a natural green diamond is extremely rare in any form.

MODIFIERS

Modifiers colours of green diamonds include brown, yellow, grey and blue. Brown and Grey are similar in that they greatly reduce the value of a stone. Stones of this nature have more tone than their saturation allows and create what most people believe are less attractive colours.

Yellow as a modifier also devalues a diamond but in some cases can create vibrant colours. These stones are extremely saturated and can be described as neon in colour. What should be searched for are stones ending with green, such as fancy intense yellow green, when one is looking for these "neon" coloured stones.

Finally blue as a modifier is the most valuable of the two hued stones. Creating colours comparable to tropical waters these diamonds are extremely rare and beautiful.

Chameleon Diamonds

Another type of diamond exists called Chameleon diamonds. These stones display a change in colour after having been stored in darkness or when gently heated. Their resting colour is usually a combination of green yellow and grey and change to a orangey yellow. What is usually searched for when collecting Chameleon diamonds is a stone that has a green base colour. (example: Greyish Yellowish Green) .

Fancy Shaped Diamonds

The fashioning of natural coloured diamonds into its final shape is a complex subject that requires years of expertise. Unlike colourless diamonds where the objective is to have the diamond show as little amount of yellow or brown as can be possible, the objective of fancy colour diamond cuts is to allow the inherent colour to come forth as strong as is possible.

The knowledge to accomplish this objective takes years of experience. Ladylux Diamonds has been involved with diamond cutters for over a decade, experimenting and honing the techniques of cutting parameters that bring forth the diamonds body colour to its fullest strength.

With that said most fancy colour diamonds are fashioned in what is known as fancy shapes. It is rare for a fancy colour diamond to be fashioned as a round brilliant cut diamond due to the fact that diamonds of this shape tend to hide colour. It is also rare for diamonds larger then 10 carats to be fashioned as a round diamond regardless of the presence or lack of colour.

The majority of the diamonds that are represented by Ladylux Diamonds are fancy shaped diamonds. Of the group of fancy shapes the majority are fashioned into what is known as a Radiant cut. This is a trade name for a diamond that GIA will call a cut-cornered rectangular modified brilliant. There are many different styles of facet arrangements as well as the length to width ratio. When a diamond is of this shape if the length to width ratio is 1.05 or less the shape is considered square. When the ratio is above 1.05 then it will be rectangular.

All other shapes are used to fashion diamonds with a fancy colour. These shapes include; pears, ovals, marquise, hearts, emerald, Asscher, cushions, princess and specialty cuts.

All the above shapes are considered to have a style of faceting that is called brilliant facets. The emerald cut and Asscher cut are the two styles that are called step cuts. Due to the optics of step cuts attaining maximum colour strength is difficult and as a result diamonds of this style with a strong colour is rare.

Due to the rarity of diamonds that exhibit a fancy colour, it is extremely critical that the planning from a diamonds rough state to the final gem quality state is paramount, in order to bring forth the Art of Nature of Natural Coloured Diamonds.

Diamond Weight

Diamond weight is expressed in metric carats. One metric carat equals 0.200 grams or 1/5 gram. There are 100 points to a 1.00 carat diamond. Accordingly a 50 point diamond is ½ carat and a 75 point diamond is a ¾ carat.

Due to the uniformity of proportions for round diamonds the carat weight and the diameter are usually predictable.

Due to the complexity of fancy shaped diamond, (any diamond shapes other then round) carat weight and millimeter dimensions are not as predictable. The majority of Fancy Colour Diamonds will be cut into a fancy shaped diamond. The following relationships are for fancy shapes with aesthetically pleasing length to width ratio for that particular shape.

Rounds

Emeralds, Radiants, & Ovals

Square Princess

Pear Billiants

Clarity

Diamond clarity is a quality of diamonds relating to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects called blemishes.

All diamonds sold by Ladylux Diamonds Inc. are graded by the GIA Laboratory. As such the following is a description of each clarity grade category with a short description of the type of inclusions that are expected to be in each clarity grade along with a brief description of how each grade is determined with a microscope, loupe or the unaided eye when viewed by the consumer.

Flawless

No internal or external visible inclusions with ten power magnification.

Externally free of blemishes, extra facets, naturals, surface graining and polish lines with ten power magnification. An existing natural or a laser inscription must be confined to the girdle without touching/penetrating the crown or pavilion. This is an extremely rare clarity grade. A diamond with this grade must have a polish grade of excellent.