Acquiring knowledge of the 4 Cs is crucial before purchasing any diamond: carat weight, diamond clarity, diamond colour and diamond cut (not shape). Other advanced characteristics of diamonds include diamond fluorescence and diamond enhancements. By understanding each diamond characteristic and knowing which questions to ask when purchasing a diamond, you are much more empowered when it comes time to make your diamond investment.
This is the weight of the diamond measured in carats. One carat is divided into 100 “points,” so that a diamond of 75 points weighs 0.75 carats. Carat weight is the most obvious factor in determining the value of a diamond. But two diamonds of equal carat weights can have very different prices, depending on their quality.
This is a measure of a diamond’s internal inclusion and impurities. A diamond that is virtually free of interior or exterior inclusions (commonly referred to as inclusion) is of the highest quality, for nothing interferes with the passage of light through the diamond.
Flawless – No internal or external inclusion inclusion.
Internally Flawless – No internal inclusion. Very rare and beautiful diamonds which are quite expensive.
VVS1, VVS2 – Very, Very Slightly Included: Very difficult to see inclusions under 10x magnification. An excellent quality diamond.
VS1, VS2 – Very Slightly Included: Inclusions are typically not visible to the unaided eye. Less expensive than the VVS1 or VVS2 grades.
SI1, SI2 – Slightly Included: Inclusions are typically visible under 10 x magnifications, SI clarity diamonds are usually of the best value since inclusions are not always visible to the naked eye and prices are reasonable when compared to prices of the VS2 clarity and upgrades.
SI3 – Slightly Included-Included: SI3 is an EGL grade and is not recognized by GIA or other gemological institutions. The SI3 clarity grade has been adopted by other labs as well. Typically an SI3 clarity grade would usually be given an I1 grade by the GIA.
I1 – Included: an I1 clarity diamond will have a visible flaw which can be seen with the naked eye, but there should only be one major flaw which is not too obvious. Overall the diamond should still look nice however I1 clarity grades vary quite a bit so one should be very careful when making a selection. If your budget only allows for an SI3 or I1 clarity diamond, be sure to examine it thoroughly before purchasing and make sure the inclusions do not detract from the overall beauty of the diamond.
I2, I3 – Included: These diamonds will have inclusions visible to the naked eye, and will have many black spots from the black inclusions and/or appear very cloudy or milky from the white inclusions, feathers and cracks.
Out of the 4 C’s, colour and cut are the two most important characteristics of a diamond. Do not compromise on colour. An “G” colour or better is usually best.
D-G: Colourless: perfect or almost perfect colour.
H-J: Near colourless: good to very good colour and this diamond may “face up” colourless when mounted, especially in white gold or platinum.
K-M: Light but noticeable yellow or brown tint. Not recommended for larger diamond stone purchases, especially in engagement rings.
Out of the 4 C’s, colour and cut are the two most important characteristics of a diamond. Do not compromise on colour. An “H” colour or better is usually best.
Many people confuse diamond cut with the shape of a diamond. Unlike shape, diamond cut is the metric used to evaluate the precision and quality of the overall cutting itself. Diamond cut is the most complex of the 4 Cs, and not even the major labs agree on how to best measure the quality of a diamond’s cut. Diamond Cut usually takes into consideration 3 criteria: Proportions, Symmetry and Polish.