The 4Cs of Diamonds
The Gemological Institute of America (GIA) created a comparison system to classify the rarity, quality and value of different diamonds. This is called the 4 Cs, which stand for Carat, Clarity, Colour and Cut.
Carat
Carat (ct or kt) is a measure of the weight of a diamond. One carat is equivalent to 200 milligrams. One carat can also be divided into 100 “points”, so for example a 0.75ct diamond is the same as a 75-point or 3/4 carat diamond.
Clarity
Clarity refers to the presence of inclusions or imperfections in a diamond. Inclusions are natural occurring characteristics such as minerals or fractures, which appear while diamonds are formed in the earth. They may look like tiny crystals, clouds or feathers and can reduce the lustre the stone produces when light passes through.
Many inclusions are invisible to the naked eye and require a closer look under an eyeglass, or “loupe”, to be seen. The Gemological Institute of America (GIA) scale starts at F, which means a flawless stone with no inclusions, and goes to I, which means inclusions are visible to the naked eye. The different grades are:
F – Flawless
IF - Internally flawless
VVS1 & VVS2 - Very, very small inclusions, very hard to locate under 10x magnification and unable to be seen with the unaided eye
VS1 & VS2 - Very small inclusions, hard to locate under a 10x and unable to be seen with the unaided eye
SI1 & SI2 - Slight inclusions, easy to locate under a 10x, but cannot be seen with the unaided eye
I1, I2 & I3 - Inclusions that are visible to the unaided eye
Colour
Although most diamonds appear white, many actually display hints of colour barely visible to the naked eye. The closer a diamond is to colourless, the rarer and more valuable it is.
Diamonds are graded on a colour scale established by the Gemological Institute of America (GIA), which ranges from D (colourless) to Z.
Diamonds with strong pure colours such as red, blue, pink and yellow are classified separately and are known as “fancies”.
Cut
The cut refers to the angles and proportions of a diamond. The angles on a diamond, known as facets, reflect light back to the eye. The better a stone is cut, the more it will show the unique play of colours, known as fire, within the stone.
Cut also refers to the shape of the stone, such as round, square, pear, or heart, for example
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Conflict Free Diamonds and the Kimberley Process
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“Conflict diamonds” or “blood diamonds” are those that are sold illegally to fund conflict. The term was created when rebels in some African countries used diamonds to finance violence by rebel movements and their allies, seeking to undermine legitimate governments.
The Kimberley Process started when Southern African diamond-producing states met in Kimberley, South Africa, in May 2000, to discuss ways to stop the trade in “conflict diamonds”.
The aim of this process is to stop the travel of rough diamonds around the world without the presence of a government-issued Kimberley Certificate, which guarantees that the diamonds or diamond jewellery are being sold from legitimate sources.