The Complete Guide to Understanding Diamonds

Buying diamonds, especially when it comes to buying diamond rings, can be difficult if you do not know what you’re looking for, therefore how can you tell if one diamond is better than another? We have produced this complete diamond buying guide to help you understand this precious stone a little better, especially when it comes to buying that special occasion piece of jewellery.


Brief History of Diamonds 

Diamonds have been around for centuries with various empires like the Romans and Egyptians being fascinated by the precious stone. 

Before diamonds end up in any jewellery, the formation of the stone itself takes millions of years and are only formed under extreme heat and pressure. The diamond materials are then forced up to the Earth’s crust.  

Diamonds have been found around the world in countries like India, Brazil, various parts of Africa and Russia to name a few. To date, the biggest diamond ever found in the world was the famous 3,106 carat Cullinan Diamond which was found in South Africa in 1905. 


Characteristics of Diamonds

Diamonds are not just pretty precious stones, they also have several other property characteristics that make them perfect for different types of jewellery.

Structure: The diamond structure is known as a diamond cubic which forms as a cubic structure within the rock making the same rigid

Hardness: Diamonds are known for being remarkably hard, however, the only thing that can scratch a diamond is another diamond. This is why it is important to correctly store diamond jewellery too.


The Important 4 C’s of Diamonds


If you are buying a diamond piece of jewellery, these are the four most important aspects you need to know. These four factors will provide you with a guideline for when you are buying any type of diamond.



The colour of a diamond does vary and can go from ‘colourless’ to ‘drawing’.

Diamond colouring has a scale from D to Z.  D means that the diamond is colourless, and Z means a stone has a yellow colouring to it. 

D also usually indicates that the stone will be more expensive.


Type                                             Colour Rating

Colourless                                   D,E,F

Near Colourless                         G, H, I, J

Faint Yellow                                K, L, M

Very Light Yellow                      N, O, P, Q, R

Light Yellow (Drawing)           S, T, U, V, W, X, Y, Z


The shape of the diamond can also have an effect as to where it sits on the colour scale.

Brilliant cut diamonds usually hide any colour better than longer thin diamonds.

Naturally certified coloured diamonds come in a ray of vivid colours such as pink, yellow, blue & orange and due to their rarity they’re more expensive.

Diamond Colour Diagram


The clarity of a diamond is all about the imperfections in the stone itself and is known as ‘inclusions’. These are naturally occurring through the formation process. The rating of clarity is done on a scale from internally flawless (IF) to included (I).


Clarity Scale

IF – Internally Flawless

VVS – Very Very Slightly Included

VS – Very Slightly Included

SI – Slight Included

I -Included


The clarity scale determines how clear the diamond appears to the human eye. It is important to note that sometimes the inclusions (flaws) are barely noticeable to the human eye and to your everyday person they would not be able to tell the difference between SI and a VVS diamond. You may want to consider this when buying any future jewellery.

Both the clarity and colour would be determined using a 10 times magnification eye loop not the naked eye.

Diamond Clarity Diagram



The cut of a diamond is arguably the most important aspect when looking to buy a piece of jewellery that includes a diamond. This is because the cut will bring out the uniqueness of the stone and give the piece of jewellery its overall look and feel. 

There are a number of different cuts of diamonds to consider including:

  • Princess
  • Cushion
  • Brilliant
  • Oval
  • Pear
  • Asscher
  • Radiant
  • Emerald
  • Marquise
  • Heart

Remember that each type of cut allows each diamond to show off its unique features.

Diamond Cut Diagram



Many people think that ‘carat’ is to do with the actual size of the diamond (height/width), however, this is not correct. When talking about carats in relation to diamonds we are actually referring to the weight. The higher the carat number the heavier the diamond.

Diamond Carat Diagram



So there you have it, a complete guide of what you need to consider when buying diamond jewellery. It is the four important areas; Cut, Clarity, Colour, and Carat that you need to consider when it comes to diamonds. Depending where the diamond sits on the different scales will also determine its price. For example a 4 carat diamond of bad colour, clarity and can be cheaper than a 2 carat diamond that is higher on the colour scale, clarity. 

However, some shops will charge more due to the size of the stone even when it is considered of lesser quality.

If you have any further questions about diamonds or any of our diamond jewellery please feel free to contact us at any point on 01296 423 198

Thanks for reading and we hope to see you soon.