Diamond jewellery buying guide

Diamonds are the epitome of luxury and elegance. No other stone is as powerful as a diamond when it comes to giving a loved one a gem that will so perfectly express their emotions. There are a few essentials you should know before buying a diamond to make sure that what you are buying is the right stone, in terms of beauty and quality.

The four ‘C’s

Diamonds come in all sorts of shapes, sizes and finishes, so finding one that's perfect for you can be found in their classification and grading. This is defined by the diamond's carat, clarity, colour and cut.

  • Carat

    The carat refers to the weight and size of the diamond, and is often referred to in points. One carat is equal to 0.2 grams in weight, or 100 points.

    Carat Points
    1 100
    34 75
    12 50
    13 33
    110 10
    120 5
    1100 1
  • Clarity

    The clarity of a diamond refers to the amount of inclusions or imperfections. While a pure, clear diamond has obvious benefits, imperfections can make your diamond unique and add character. Our grading follows the Gemological Institute of America guidelines.

    Grade Meaning Description
    FL Flawless An absolute pure diamond
    IF Internally flawless Surface blemishes only, internally pure
    VVS1 Very, very slightly included Minute imperfections that are difficult to spot at 10x magnification
    VVS2 Very, very slightly included As VVS1, but imperfections are slightly easier to find at 10x magnification
    VS1 Very slightly included Minor imperfections that are difficult to spot under 10x magnification
    VS2 Very slightly included Minor imperfections that are easier to find under 10x magnification
    SI1 Slightly included Imperfections that are easy to see under 10x magnification
    SI2 Slightly included Imperfections that are very easy to see under 10x magnification
    I1/PK1 Included Obvious imperfections, not affecting the brilliance of the diamond
    I2/PK2 Included Obvious imperfections, affecting the brilliance of the diamond
    I3/PK3 Included Obvious imperfections that can threaten the diamond's durability
  • Colour

    Diamonds are known for their crystal clear appearance, but in actual fact they can be found in any colour. Some colours are scarcer than others, but in general the clearer a diamond is the rarer it is. As with the clarity, the colour of a diamond is also graded.

    Colour Grade
    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 S, T, U, V, W, X, Y, Z
  • Cut

    Brilliant, round cut diamonds cause the light to be reflected from within, for the beautiful, glittering shine diamonds are renowned for. Diamonds come in many other cuts, such as princess, emerald and heart cuts, to perfectly suit the jewellery and occasion.

The Kimberley Process Certification Scheme

Tesco and our suppliers support the Kimberley Process, ensuring our diamonds come from a reliable source and were not illicitly traded.

All vendor invoices for Tesco Diamond Jewellery contain the following statement:

“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.”