The 4 C's of diamonds are: Cut, Colour, Clarity and Carat Weight. The main grading authorities are the G.I.A - Gemological Institute America, HRD - Hoge Raad Voor Diamant vzw, IGI - International Gemological Institute or SureCert which specifies the diamonds colour, cut, clarity and carat weight, plus polish and symmetry grade among other details.
Diamonds are cut from rough in to various shapes to retain the maximum carat weight from the stone. The higher the grade of cut enables the maximum refraction and reflection of light passing into and back out of the stone.
Heart & Arrow Cut
This is the highest cut available to ensure intense fire and brilliance from a diamond.
The Hearts and Arrows diamond gives the impression of arrows when viewed from the top, and hearts when viewed from below.
When a diamond has a high quality cut (Very good / Excellent), the light will enter through the top, where it reflects from one side to the other before bouncing back out of the diamond's table toward the observer\'s eye in an even dispersion. This phenomenon is referred to as "light return" which affects a diamond\'s brightness, brilliance, and dispersion.
Not only do Hearts and Arrows diamonds appear more brilliant, they can also appear larger than other stones of the same carat weight. An ideal stone has both increased brilliance as well as increased diameter relative to more deeply cut diamonds.
Clarity refers to the presence (or absence) of impurities, blemishes or other identifying characteristics within a diamond. Clarity characteristics are what make every diamond completely unique. There are no two diamonds that will have exactly the same inclusions in the same location.
The standard high street clarity is I1 (eye 1), as marks can generally not be seen with the naked eye. The below image shows the different grades, and are represented by red marks on the diagrams.
Clarity is graded as follows:
IF - Internally Flawless
The diamond has no inclusions when examined by an expereinced grader using 10x magnification.
VVS1, VVS2 - Very Very slightly included
The diamond contains minute inclusions that are very difficult even for experienced graders to see under 10x magnification.
VS1, VS2 - Very slightly included
The diamond contains minute inclusions, which are barely noticeable when observed under 10x magnification.
SI1, SI2 - Slightly included
The diamond contains inclusions that are noticeable to an experienced graded under 10x magnification, but not visible by the naked eye.
I1, I2, I3 - Included
The diamond contains inclusions that are easily noticeable under 10x magnification. I1 clarity is generally clean to the naked eye, but lower grades I2, I3 will be visible to the naked eye.
Diamonds are certificated by various laboratories around the world and here is a selection of the most popular and well respected ones which will give you peace of mind when purchasing your diamond jewellery.
A well respected laboratory in the UK that recognises the hearts and arrows standard of superior diamonds. Due to them being based here in the UK, these diamonds are generally lower priced than their American counterparts.
The Gemological Institute of America is the largest and most respected laboratory in the USA, and a good choice for your diamond purchase. They are slightly higher priced than SureCert diamonds because of their import into the UK.
Hoge Raad Voor Diamant vzw which is the Belgian High Council Diamond Grading Laboratory in Antwerp.
The International Gemological Institute.
When shopping for a diamond, it is generally preferred to have the least amount of color possible. The standard high street colour is I (eye), as diamonds graded below noticable yellowing features to them. Diamond colour is divided into three broad categories:
Colourless (D-F): Diamonds within the colorless range are the most rare and valuable of all the colors. D/E color stones display virtually no color, whereas F colored diamonds will display a nearly undetected amount of color when viewed face down by a gemologist.
Near Colourless (G-I): Diamonds within the near colorless range appear colorless in the face up position, but do display a slight amount of color when viewed face down against a perfectly white background. This trace amount of color is undetectable to an untrained eye once the diamond has been mounted. Near colorless diamonds offer a tremendous value for the money.
Coloured (J+): Diamonds out of the colourless range have an increasing faint yellow appearance which detracts slightly from the pure brilliance of the diamond.
Diamond weight is measured in carats, a small unit of measurement equal to 200 milligrams. Each carat is divided into 100 points. Therefore, a half-carat stone may be referred to as a "50-pointer" or "50-points". Carat weight is the easiest of the 4 C's for gemologists to determine because of the use of sophisticated measuring equipment.
Two diamonds of equal carat weight might vary greatly in value depending upon their cut, color and clarity. This is important because when mounted, one diamond may appear larger than the other, although they actually weigh the same. Because large diamonds are rare, they generally have a greater value per carat. For example, the price of a two-carat stone will be several times higher than four 50-pointers of equal quality.
Platinum is 30 times rarer than gold, but this precious metal's most appealing characteristic may be its durability. When other metals are scratched or polished, tiny bits of the metal may be lost. A scratch in platinum may leave a mark on the metal, but this metal is so strong that it will not readily chip or splinter. Even very slim platinum designs will permanently retain their shape. For that reason, platinum makes an excellent overall choice for jewellery.
Platinum is a great choice for jewellery. It is hypoallergenic because of its purity, and will keep its natural white forever with moderate care.
Platinum is the strongest of jewellery metals, but it will eventually develop a motled look. Many people prefer this unique look, but if you prefer the shine, a jeweller can polish your jewellery to bring back the original reflective finish. In the mean time, buffing with a soft cloth can give your jewellery renewed lustre.
Gold won't tarnish, rust, or corrode, and though it's very strong, it is also the most malleable of all metals. Pure gold is too soft to withstand the stresses of daily wear, so it is alloyed with a mixture of metals like silver, copper, palladium, and zinc to give it strength and durability. Caratage indicates purity and is noted by a number followed by the letters "CT". Traditionally caratage is expressed in 24ths, meaning 18k gold is an alloy of 18 parts gold and six parts other metal. 24k gold is 100% gold with no alloyed metals.
There are three compulsory hallmarks applied to precious metals as a quality control: a sponsor's (maker's) mark, a fineness mark, and an assay office mark. These marks establish the origin and fineness of the precious metal and ensures it has been accurately and independently tested.
There are few exemptions to the hallmarking laws. One exemption is by weight; compulsory hallmarks are not needed on gold under 1g, silver under 7.78g and platinum under 0.5g. Also, the UK is required by the European Court of Justice to accept other European national hallmarks as sufficient hallmarking, providing those hallmarks represent an equivalent guarantee of quality. All products sold by Alba Rose comply with current Parliamentary nickel regulations.