Engagement Rings - The 4Cs of Diamonds

The diamond in your Engagement Ring

Key considerations when looking to choose diamonds for engagement rings are the ‘4Cs’:

The Cut of a Diamond determines its “sparkle”, or more technically speaking its “fire and brilliance”. A diamond that has an “excellent” cut will give a greater return of light which is what creates the enchanting sparkle. Diamonds that have a poor cut are those which have been cut too shallowly. This is apparent because they will not reflect the light and will have dulled brilliance. The diamond cut grading scale is as follows: excellent, ideal, very good, good, fair and poor. It is recommended that you buy within the “excellent” to “very good” range for engagement rings.

Diamond Colour describes whether the diamond is colourless or “white”, i.e. essentially transparent, or, at the other end of the scale, has noticeable colour and appears light yellow or brown. The colour in diamonds is caused by impurities such as nitrogen, and structural imperfections. This effect is present in almost all diamonds with only the rarest showing no signs of colouration. The colour of a diamond has a direct bearing on its price: the whiter it is, the more expensive it will be. Again diamond colour is graded on a scale of D to Z with D being colourless and Z showing noticeable colour. When deciding what colour grade to purchase for engagement rings the ideal is in the colourless D-F range. However, note that to the untrained eye and without the use of specialist equipment, the colour difference compared to the near colourless stones in the G-H range is barely perceptible. The difference in price is significant too; a 0.5ct round brilliant diamond with a D colour could cost you over $1000 more than a 0.5ct with an H colour.

Diamond Clarity refers to how many flaws or “inclusions” a diamond has. Diamonds are graded on a scale from F - flawless, to I1-I2-I3, where flaws are clearly visible to the naked eye. A VS1 - VS2 grade (very slightly included) means you won’t be able to see any flaws in the diamond with the naked eye. A SI1-SI2 grade (slightly included) will start to have a few flaws that will be visible to the trained eye. A diamond with clarity in the VS2-SI2 grade range will offer affordability and a great stone. It is often not worth paying the high price for a near flawless or flawless diamond if it cannot be appreciated as such by the naked eye. For engagement rings with a diamond less than one carat in weight, SI1 is perfectly acceptable. Above that size, it's probably best to insist on VS2 or better.

Diamond Carat Weight (Size) is often taken to be the most important consideration when purchasing a diamond for engagement rings. However, as above, remember that diamonds of the same size can vary in price according to their quality, which is also measured by colour, clarity and cut. There are two common ways of referring to carat weight: total-carat-weight which refers to the combined weight of several diamonds in a multi-stone ring; and centre-stone-carat-weight which refers to the carat weight of the main stone (which may also be the only stone). Although it is true to say that typically the larger the carat weight the more expensive the diamond, this can be something of an over-simplification. A ring that has a lot of small cheap diamonds may have a total-carat-weight of 1.0 carats but this cannot be compared to a ring that has a single 1.0 carat stone which is considerably more rare, and substantially more expensive.