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Established in 1980, Paul Carruthers Manufacturing Jewellers are committed to producing unique and beautiful jewellery of the finest quality.
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Paul Carruthers Manufacturing Jewellers offer a wide range of services, including Jewellery Manufacturing, Restoration, Cleaning and Valuations for Insurance.
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Diamond Ring

The diamond symbolises eternity, strength, purity, beauty, love and commitment.

Paul Carruthers Manufacturing Jewellers are passionate diamond specialists, sourcing the finest conflict-free certified quality diamonds from the cutting centres of the world. The company has made its name by specialising in the most beautiful of gemstones.

The majority of our diamonds have been scientifically certified in independent diamond laboratories worldwide such as the GIA (Gemological Institute of America), HRD (Antwerp World Diamond Centre, Belgium) and GSL (Gem Studies Laboratory of Australia). We also have a wide range of diamond jewellery available.

Understanding Diamonds

When purchasing a diamond there are four main characteristics to take into consideration ("The 4 Cs"):

Carat Weight: Weight of stone
Cut: Proportions and finish
Clarity: Natural inclusions
Colour: Level of colour

Carat Weight

The carat is an ancient unit used to determine the weight of gemstones. Carat weight is expressed as points where 1 carat = 100 points = 0.200gram. Therefore if a diamond is 50 points it weighs 0.50 of a carat (half a carat) or if the diamond is 75 points it weighs 0.75 of a carat (3/4 carat) and so on.

Although size is considered a major determining factor in the value of a diamond it doesn’t always equate to greater diamond value. Two diamonds of equal carat weight may have vastly different values depending on the cut, colour and clarity.


The cut of a diamond is the most critical factor in the overall beauty of a diamond as the cut will determine how well a diamond reflects light. A stone of high colour and clarity may still appear dull and lifeless if it is of a poor cut, which in turn can greatly affect its beauty and value.

When a diamond is cut to optimise light performance it is said to be of ideal proportions. The quality of the cut refers to the measurements of the diamonds proportions, the symmetry of the facets and the quality of the polish. When a diamond is cut to excellent proportions, light is reflected from one facet to another and dispersed through the top of the stone ensuring maximum light return, a myriad of colours, brilliance and fire.

Different shapes of diamonds include Round Brilliant, Princess, Cushion, Square, Emerald, Marquise, Heart, Pear and Baguette, just to name a few.


The standard for clarity grading diamonds has been set by the high quality diamond loupe of 10x magnification. Under magnification diamonds may display various types of internal irregularities (called internal characteristics or inclusions) or external irregularities (called external characteristics or blemishes).

Clarity grading uses a series of abbreviations to denote number, size, location, type and intensity of inclusions and blemishes. Diamonds with fewer inclusions are rarer and therefore more valuable. As the grade of clarity lowers in the diamond the more natural inclusions it will have. Large inclusions can obstruct the light paths of the diamond, resulting in reduced transparency.


To discern the colour of a diamond the international colour grading system uses the letters D to Z, where D is colourless and the depth of colour increases down the scale to Z. These grades are set in relation to a series of master diamonds maintained by the credible grading labs throughout the world such as the Gemological Institute of America.

Apart from colourless (white) diamonds, there are also natural pure coloured diamonds known as "Fancy" coloured diamonds such as pink, blue, green and yellow. Be aware that there is also an array of treated coloured diamonds available.

Need to know more?

Choosing diamonds can be often be a big and important decision, so please feel free to contact us if you’d like to have a chat about what sort of diamonds could be right for you.