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Guide to buying diamonds

Does the idea of purchasing a diamond engagement ring engulf you? Maybe you feel you do not possess adequate knowledge about diamond cuts, shapes, certificates, grading scales or colours to make a well well-informed decision. Well there’s good news — contradictory to what some sales people and websites will promote, buying a diamond or perfect diamond encrusted eternity ring is not as daunting as you have been led to believe.

If you desire to study the basics of buying a diamond before purchasing your diamond eternity ring or diamond engagement ring, begin with our segment on the "4 Cs of diamonds".

Most individuals who obtain diamonds as a gift or for an upcoming engagement usually have apreference of shape. Although other factors (for instance, price and quality) should be resolute, the selection of shape should ideally be from the recipient of the diamond where possible, in particular with fancy shaped diamond engagement rings.

Unless a specific preference has been voiced, we usually advice considering a round/solitaire diamond stone. Round diamonds have a tendency to have more brilliance and sparkle than other shapes; they acclimatise almost any ring setting and at no time go out of fashion.

These are some of the most popular diamond shapes, celebrated worldwide. 

  • Asscher Cut Diamonds
  • Cushion Cut Diamonds
  • Emerald Cut Diamonds
  • Heart Shaped Diamonds
  • Marquise Cut Diamonds
  • Oval Diamonds
  • Pear Shaped Diamonds
  • Princess Cut Diamonds
  • Radiant Cut Diamonds
  • Round Brilliant Diamonds

When acquiring certified diamonds it is imperative to comprehend the diamond grading standards utilised by laboratories carrying out the certification.
Diamond grading covers ample aspects of each distinct diamond's potentials, but there are four grades which are important to understand:

  • Cut
  • Clarity
  • Colour
  • Carat

Although there are added ratings and dimensions eminent on a diamond certificate, they commonly fall below one of these 4 categories (the "Four Cs"). For instance, dimensions such as "depth" and "table" form aportion of the description of the diamond's cut.

Cut is perhaps the most important quality factor and the most puzzling of the four Cs to understand. The brilliance of a diamond profoundly depends on its cut. Since cut is so significant, numerous grading techniques have been established to help customers define the cut of a specific diamond. In general, the grades are as follows:

  • Ideal
  • Excellent
  • Very Good
  • Good
  • Fair & Poor

Most diamonds embrace some internal flaws (or inclusions), that take placeduring the development process. The perceptibility, number and size of these inclusions isreferred to as the ‘clarity of a diamond’. Diamonds that are unblemishedcreate extra brilliance thus, are extremely priced and prized.
Clarity has been defined using the following scales within the world of diamonds.

  • IF Internally Flawless: No internal flaws. Very rare. 
  • VVS1-VVS2 Very Very Slightly Included (two grades). Minute inclusions very difficult to detect under 10 x magnification by a trained gemmologist. We do not recommend any diamond grades below this grade from and above 0.50 CT.
  •  VS1-VS2 Very Slightly Included (two grades). Minute inclusions seen only with difficulty under 10x magnification. We do not recommend any diamond grades below this grade.
  •  SI1-SI2 Slightly Included (two grades). Minute inclusions more easily detected under 10x magnification.
  •  I1-I2-I3 Included (three grades). Inclusions visible under 10x magnification AS WELL AS to the human eye.



When jewellerspitch of a diamond's Colour, they are generallydenoting the absence or presence of Colour in white diamonds. Colour is an outcome of the configuration of a diamond and it by no means changes over time.
For the reason that a Colourless diamond, like a flawless window allows far more light to pass through it, Colourless diamonds discharge more sparkle and brilliance. The development process of a diamond guarantees that only a few, rare diamonds are truthfullyColourless. Thus, the whiter a diamond's Colour, the superior its value.

A carat is the unit of weight through which a diamond is measured. Since large diamonds are found less frequentlyin comparison to smaller diamonds, the worth of a diamond rises exponentially to its size.

Also referred to asa ‘grading report’, a diamond certificate is a complete assessment of your diamond. These certificates from esteemed laboratories have been executed by a skilled professional with the aid of exceptionalgemmological instruments. Each stone bears its own distinguishable and individual physiognomies, which is listed on the certificate document.

Reluctantly the size will ultimately be dictated by your budget, therefore we advise our customers to first decide on what they wish to spend. If you are buying for your loved one a diamond engagement ring, pre-set diamond engagementring, diamond eternity ring or a piece of diamond jewellery, you will want to ensure your budget is suffice to avoid any disappointment. For many this will be a once in a lifetime purchase.
Once your budget has been decided you can start to select your preferred cut, clarity, colour and carat.

Ring Size Guide

International ring sizes

Other countries use a different scale to the U.K; you can use the table below to help you decide which size you need

 Circumference (mm) Diameter (mm) Europe UK & Australia US & Canada
44.2 14.1 44 3
44.8 14.3 45 G  
45.5 14.5  
46.1 14.7 46 H  
46.8 14.9 47 4
47.4 15.1   I  
48.0 15.3 48 4½<
48.7 15.5   J  
49.3 15.7 49 5
50.0 15.9 50 K  
50.6 16.1  
51.2 16.3 51 L  
51.9 16.5 52 6
52.5 16.7   M  
53.1 16.9 53
53.8 17.1   N  
54.4 17.3 54 7
55.1 17.5 55 O  
55.7 17.7  
56.3 17.9 56 P  
57.0 18.1 57 8
57.2 18.2      
57.6 18.3   Q  
58.3 18.5 58
58.9 18.8 59 R  
59.5 19.0   9
60.2 19.2 60 S  
60.8 19.4 61
61.4 19.6   T  
62.1 19.8 62 10
62.7 20.0   U  
63.4 20.2 63 10½
64.0 20.4 64 V  
64.6 20.6   11
65.3 20.8 65 W  
65.9 21.0 66 11½
66.6 21.2   X  
67.2 21.4 67 12
67.8 21.6   Y  
68.5 21.8 68 Z 12½
69.1 22.0 69 Z  
69.7 22.2 70   13
70.4 22.4   Z+1  
71.0 22.6   Z+2 13½