Diamonds all the information

The four basic rules that determine a diamond’s value are known as the 4Cs. Carat, Cut, Colour, Clarity and Carat are standards throughout the world used to describe diamonds. But what do these words actually mean? How can they help you choose the perfect diamond engagement ring? We’re here to answer all your questions to help you find a diamond engagement ring she’ll love forever.

Take a few moments to read over these brief descriptions regarding: carat weight, cut, colour, clarity and certificate.

Carat Weight

The Carat is a unit of weight for precious stones equal to 200 milligrams, 1/5 of a gram. Price is exponential and is based on size. A 1-carat diamond could cost 10 times that of a 1/4 carat due to the rarity of its size.

Carats refer to the size of the diamond. Each carat has one hundred points. The carat weight refers to the mass of a diamond, for example, a diamond that is a 1/2 carat can be referred to as a 50-point diamond.


Cutting of a diamond takes extreme precision and patience. Perfectly cut diamonds will reflect light entering from the top or "table," refract the light in a balanced manner throughout the diamond, and exit the light back out through the top portion of the diamond. The quality of a diamonds cut and its proportions can have a significant effect on its price.

To achieve an ideal or perfectly cut diamond, more of the raw material or "rough" is lost in the cutting process, which creates a higher cost for the diamond from the onset of the cutting process. This also explains why all diamonds are not perfectly cut.

The most common form of diamond cut is the round one, called brilliant. This term identifies a round cut with 57 facets minimum, to which is added a culet (not always present).  Other types of cut, among the most popular and widespread are: heart, oval, marquise or navette, princess, cushion, emerald, pear and asscher as shown here.


Diamonds come in a variety of colours, some of them highly prized (pinks, blues, even yellow). However, in a white diamond, the presence of a yellow tint will lower the price of a diamond. The less body colour in a white diamond, the truer colour it will reflect, the rarer and more valuable it is in most cases. Some diamonds come out of the ground with very vivid and well-defined colours. These diamonds are extremely rare and valuable.

 Diamonds of D, K, and Z GIA Colour Grades

 Diamonds of D, K, and Z GIA Colour Grades

The diamond industry has adopted the GIA diamond colour scale; almost every diamond sold today is rated using the GIA colour scale, whether it was actually certified by the GIA or not.

The GIA grades diamonds on a scale of D (colourless) through Z (light colour). All D-Z diamonds are considered white, even though they contain varying degrees of colour. True fancy coloured diamonds (such as yellows, pinks, and blues) are graded on a separate colour scale. 


Every diamond is unique with distinctive internal and external characteristics. Because diamonds formed deep within the earth, under extreme heat and pressure, they often contain unique birthmarks, either internal (inclusions) or external (blemishes).

Diamond clarity refers to the absence of these inclusions and blemishes. Diamonds without these birthmarks are rare, and rarity affects a diamond’s value. Using the GIA International Diamond Grading System™, diamonds are assigned a clarity grade that ranges from flawless (FL) to diamonds with obviousinclusions (I3).

For all grades except I1, I2 and I3, a 10 power magnification microscope or loupe (pronounced "loop") is used to observe the diamond to decide its clarity.


Diamonds frequently have inclusions, or small flaws, air bubbles, scratches or other minerals which lower the transparency and decrease the amount of light that can be transmitted through the diamond. The less inclusions a diamond has, the more valuable and beautiful it is.

Conflict Free

The Kimberley Process is a joint governments, industry and civil society initiative to stem the flow of conflict diamonds – rough diamonds used by rebel movements to finance wars against legitimate governments.  All the diamonds we use are from British sellers that provide on their invoices a Kimberley Process Warranty.

"The diamonds herein invoiced have been purchased from legitimate sources not involved in funding conflict and in compliance with United Nations Resolutions. The seller hereby guarantees that these diamonds are conflict free, based on personal knowledge and/or written guarantees provided by the supplier of these diamonds.“

The Kimberley Process – covers 99.8% of all diamonds traded globally. The diamond industry says that one conflict diamond is one too many and it will not rest until they are eradicated completely. 

The Diamond Development Initiative International (DDII) is a unique effort bringing NGOs, governments and the private sector together in a common effort that aims to ensure that diamonds are an engine for development. They envision “development diamonds”, as diamonds that are produced responsibly, safely, with respect of human and communities’ rights, in conflict-free zones, with beneficiation to communities and payment of fair prices to miners. Jessica Flinn Designs Ltd supports the work of the DDII and it's positive work to help diamond miners and their communities in Africa and South America. DDII Facebook page .