Diamond buying guide

There are many beautiful gemstones that have been created by nature and mined from the earth but the most regal of them all is the diamond. The mysterious diamond is the most popular gemstone of them all and the one that has the most myths and legends associated with it.
Diamond buying guide


There are many beautiful gemstones that have been created by nature and mined from the earth but the most regal of them all is the diamond. The mysterious diamond is the most popular gemstone of them all and the one that has the most myths and legends associated with it.

'Diamond' derives from 'Adamas', the Greek word meaning 'invincible', a reference to the hardness of a diamond's form. Over the centuries the diamond has been a symbol for strength, luxury, beauty and commitment. Nations have gifted diamonds to other nations as a measure of friendship and respect. Lovers have gifted diamonds to seal their promises to one another.

Diamonds have been prized and coveted for centuries, and until the 19th century were mainly the preserve of the rich, landed gentry or royalty. Today however everyone can enjoy the beauty of this complex stone.

Before making the decision to purchase your very own piece of history and start to make your own memories you should delve into the enthralling history of this precious stone.

Our Diamond Buying Guide will giving you the knowledge and confidence you need to choose your own beautiful item of diamond jewellery.

The Four Cs

Cut, Colour, Clarity, Carat Weight.

The Four Cs are essential for getting to know the elements of your diamond jewellery. For a first-time buyer, you might feel that you need to add a fifth C - 'Complicated' to the list. This however is not necessary, we want to take the complicated out of the frame and help make purchasing your special diamond engagement ring a pleasure. A complication that can often come into the process is affordability, however you can rest assured, beautiful diamonds can fit almost any budget.


The cut of a diamond is a term often confused with shape but in diamond terms the cut is the proportion, symmetry and finish created by a skilled diamond cutter to bring out the full beauty of the diamond. It’s a bit like a trip to the hairdressers, if the cut is good, you look and feel great, if it is a bad cut your hair can be spoilt. Hair grows again though, once the cutter has cut the stone there is no going back so the skills of the cutter determine the way the diamond handles light giving it more sparkle and brilliance. When shopping for your diamond we have included information for each diamond's cut on the product page.


When we speak of a diamond’s colour we are referring to the presence or absence of colour in white diamonds. Jewellers use the alphabet to grade diamonds starting with D, the very rare colourless diamond, moving through the alphabet as the colour exhibited becomes more visible.

Natural fancy coloured diamonds are much sought after and the exquisite colours and rarity of these stones makes them a premium product and highly desirable and cherished. There is a truly amazing spectrum of colours for diamonds, boasting everything from yellows, blues, pinks, reds and greens. Nature really out did itself.


Clarity is another important factor when buying a diamond as this refers to the presence of inclusions inside the diamond such as non-diamond mineral. These will display themselves in the form of white or black marks. These non-diamond minerals have been caught in the process of the diamond being formed deep under the earth. Different parts of the world have different mineral deposits so diamonds from India may have different mineral inclusions to diamonds from Australia. Sometimes gasses get trapped and these interrupt the carbon atoms sometimes causing feathering or white inclusions.

Diamonds are graded from Flawless to Included (with grades in between) and these grades refer to the level of inclusions within the diamond and whether they can be seen using a jeweller’s eyeglass or with the naked eye alone.

The clarity grade chart most often used today is the GIA grading as below


Inclusions are natural characteristics that can be seen within the diamond.

Flawless diamonds are very rare so from a commercial aspect jewellers start at IF which stands for internally flawless and no internal inclusions can be seen using a 10X jeweller’s eyeglass.

  • VVS stands for very very small inclusions seen with a 10X eyeglass.
  • VS very small
  • SI small inclusions seen with the eyeglass but still eye clean to the naked eye.
  • I diamonds, included, have inclusions that can be seen by the naked eye but often you have to look very carefully to see them.

A good diamond cutter can limit the impact of the inclusion and a diamond setter can also make a difference by setting the diamond to show off its natural beauty. There are no imperfections when it comes to diamonds.

These inclusions are what make diamonds so fascinating as, unless the stone is certificated as Internally Flawless, each diamond will have its own unique properties, making no two the same. As a buyer, this means you are given the opportunity to own a truly unique piece of natural history.

Carat Weight

The carat weight of a stone may be expressed as carats or points but they are both the same. 100 points make up a carat which can written as 1.00 carat. Half a carat may be 50 points or 0.50 carat. A one carat diamond weighs one fifth of a gram.

The word carat originates from the Greek and Arab names of the carob or locust tree (Ceratonia siliqua and Qirrat, respectively). Early traders used the seeds of the Carob tree as counterweights when weighing gold or gemstones as their weight is fairly consistent at around 0.20 gram.

Carat weight is a term only used for gold and gemstones giving these beautiful items their own special system of measurement.


Some diamonds today have a certificate that includes a report of the individual four cs relating to the diamond, along with and analysis of the cut grade and any other characteristics that the graders feel are relevant.

All diamonds in the Nightingale Signature Collection, Arctic Brilliance, Passionate Heart, Coloured and Lab collections have their own certificate, a unique and unbiased professional report detailing the examination the gemstone has undergone.

Caring for your diamond jewellery

Diamonds are the hardest mineral known to man but on occasion they may become scratched or damaged if subjected to pressure on vulnerable points so it is advisable to take some care when wearing your jewellery.

We recommend removing your jewellery if using chemicals, doing heavy work such as gardening or DIY and generally being mindful of your treasured possession.

Here are some tips to keep your diamonds sparkling:

  • Avoid contact with chlorine bleach, this may pit or discolour the mounting.
  • Avoid wearing your diamonds when doing heavy work, a diamond may be chipped with a blow against the grain.
  • Diamonds can scratch each other so place in padded boxes when not wearing them, separate from other jewellery to avoid scratching.
  • Keep your diamonds clean by washing in a bowl of warm water with a liquid detergent, brushing gently with a clean soft toothbrush. Place in a small wire strainer (a tea strainer is perfect for this) and rinse well before patting dry with a soft, dry, clean cloth. If using a sink ALWAYS put the plug in. Our advice is to use a small bowl to avoid any accidental loss of small items down the plughole.

Myths and legends

It is thought that the first diamonds discovered were extracted from river-beds in India in about 400BC and discovered manuscripts seem to support this. The ancient Hindus valued the gem for its indestructibility and admired it for its ability to reflect light. They set diamonds into the eyes of statues, as they believed that the stones had the power to ward off evil.

The Hindus were not the only people to believe diamonds had mystical origins, the ancient Greeks believed diamonds were the tears of Gods and the Romans believed they were shards of stars. Plato considered diamonds to embody human spirits and other ancient cultures thought that they were dew drops that had been solidified and turned into diamonds by unknown forces.

In ancient times there were no tools available that could cut a diamond and this was another reason the ancients believed the diamond had supernatural powers. Diamond was also believed to have the power to heal, bestow wisdom and seduce. At one time, the power of diamonds was considered so strong that only men of royal blood were considered worthy of them. Diamonds were very much associated with men of courage and monarchs wore them in their swords and clothing as a sign of both power and courage.

In the Middle Ages, the diamond was thought to protect the wearer against the plague. Queen Elizabeth I is reported to have worn one on her body to guard against infection. Napoleon, another believer in the mystic powers of the diamond, had the famous Regent diamond in the hilt of the sword he carried at his coronation.

Romance and diamonds

It is a tradition that an engagement is celebrated with the giving and accepting of a betrothal ring. Anthropologists believe this tradition originated from a Roman custom in which wives wore rings attached to small keys, indicating their husband’s ownership. It is believed that the more modern engagement tradition began in 1477 when Archduke Maximillian of Austria commissioned the very first diamond engagement ring on record for his betrothed, Mary of Burgundy. This simple gesture began the trend for diamond rings among European aristocracy and nobility.

Centuries passed until the sentimental Victorians popularised ornate engagement ring designs that mixed diamonds with other gemstones, precious metals and even enamels. Often these rings were crafted in the shapes of flowers and were called “posy rings.”
Diamond rings crafted during the Edwardian era continued the tradition of pairing diamonds with other jewels, commonly mounted in filigree settings.

The history of the engagement ring, as we now know it, probably began in the 1930s.

However one thing is certain, whatever the traditions over the years the diamond engagement ring still reigns supreme as the choice of most engaged couples.

Fascinating Fact

It is interesting to know that Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in structure. The graphite in pencils is the same element as a diamond. It is the way that the earth has acted that makes the difference from a lump of fossil fuel to a stunningly beautiful and scintillating gemstone. Diamonds are the hardest mineral known so it is fascinating that graphite is so soft, diamond so hard, but they both are formed from the same chemical element.

Further reading


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