Tips and Tricks

Loose Diamonds: A Buyers Guide

The 5 C's

Cut, Color, Clarity and Carat weight are the famous four C’s. These are the characteristics of a diamond that are measured and determine the stone's final price. When looking to buy loose diamonds, it is important to look at all of these aspects as well as how they interact with each other.

The 5th C you ask? Well, it is Certification. Many times loose diamonds are certified so that we can see each specific stone's information and characteristics. A certification you may have heard of is the GIA. They have a database of their diamonds where you can check out the different parameters of each stone. Certification of stones is important and gives a good idea about how the diamond looks and its worth.

The color of the diamond is graded D-Z color. D being the most colorless and Z being a diamond saturated with color (brown, yellow, grey or otherwise).

Rare Carat Diamond Color Guide showing Colorless (D, E, F) Near-Colorless (G, H, I, J) and Very Faint Yellow (K, L, M) color range

Clarity constitutes the natural inclusions within the stone making it unique and is graded on a scale of Flawless to "I" clarity which are inclusions (black, white or otherwise) that you can clearly see with the naked eye. Some people tend to like lower color stones as they have a warmer tone to them and are price friendly, though near colorless stones are always desirable and a fine investment.

A chart showing the different clarity grades for a diamond FL - I3

In terms of the cut of the stone, well all of them are pretty, and it's completely up to you, but there are a few things to keep your eyes open for. First, make sure to only get a diamond with an Excellent cut grade (round shape only) - since this is where all of the sparkle and shine comes from! Next, don't go any lower than Very Good for the polish and symmetry (applies to all shapes). Finally, consult the ideal proportions we recommend for the shape you're interested in to ensure you get a fabulously cut diamond for maximum sparkle and shine.

Rare Carat round diamond cut chart showing Rare Carat Ideal, Excellent, Very Good, Good, Fair, and Poor diamond cuts


Fluorescence, although less visible to the eye most of the time, is still something important to look for as it affects the value of your diamond. Fluorescence is the reaction of the diamond to UV light and is rated on a scale of none to very strong (usually blue, but can sometimes be other colors like yellow, orange or green). Sometimes on a lower color stone (H-Z), fluorescence can make it appear whiter, while on a colorless stone a strong fluorescence can give a cloudy appearance.

Diamond graphic showing different color grades. DEFG undesirable if strong fluorescence present. H or lower helps to mask warmth

By checking the 4 C’s and the other parameters of a diamond’s certification you can get a good idea as to what the stone will look like and if it's different characteristics are considered desirable and of good make and value.

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