The true value of a diamond lies in its rarity. Every diamond has its own unique set of characteristics defined by the 4Cs: Colour, Clarity, Carat and Cut. These in combination are what define a diamond’s true value.

23 shades of white
The colour of a diamond varies from brown to very rare pinks, blues and greens. While yellow is the most common variety, the best colour for a diamond is white or colourless. Such diamonds are extremely rare. Diamond shades are graded from D to Z, with those graded D being the rarest.

Flawless brilliance
A diamond’s clarity is a description of its internal purity. Almost all diamonds contain non-crystallised carbon or other minerals known as inclusions. The fewer and smaller the inclusions, the purer the diamond and the greater its clarity as more light will pass through it. The clarity of a diamond is graded according to its inclusions. A diamond with zero inclusions is considered Flawless.

A cut above the rest
A diamond’s brilliance and value is determined by its cut rather than its shape. When a diamond is cut well by a master diamond cutter, it acts like a mirror, refracting light all around. This increases the stone’s brilliance and enhances its exquisite beauty.
The most popular shapes of diamonds are:
Round Brilliant, Oval, Marquise, Pear, Heart, Emerald, Princess, Radiant

A measure of perfection
A diamond’s weight is measured in carats. One carat is equivalent to 0.2 grammes or one hundred points. However, the more points or carats a diamond has does not necessarily reflect a greater value. This is still dependent upon a combination of its colour, clarity and cut.

Coating
A pearl is formed by layered coatings of nacreous secretions over a nucleus. It takes thousands of crystalline layers to form a pearl. The quality of a pearl’s coating depends on the thickness, fineness and smoothness of these layers.

Lustre
This is the sheen that reflects light on the pearl’s surface. Lustre is a result of two types of light – that reflected by the pearl’s surface, and that reflected by crystal layers within the pearl. When these two types of light intersect, they reflect the depth of lustre and the pearl’s shimmer. The finer and thinner the layers are on a pearl, the greater its lustre.

Colour
The colour of a pearl is determined by the colour of its layers, which can range from red to yellow and even green, and the refraction of light through these layers. Black pearls can have coloured layers ranging from black, green, red, grey, blue, white and peacock green.

Size
Size is one of the most important criteria for evaluating black pearls. Cultivated for an average of two years, these pearls generally grow by 0.7 mm to 1 mm a year. Harvested pearls average 9–14 mm in size, though advances in cultivation technologies have produced even larger pearls.

Shape and flaws
Black pearls are classified in the following six shapes: round, drop, oval, circle, baroque and Keshi. As black pearls characteristically have warps and flaws, which occur during nacre (layer) formation, the smoother the black pearl, the rarer and more valuable it is. Smooth, drop-shaped pearls have become highly valued in Europe and the US.

Matching
Black pearl necklaces contain pearls matched in colour, shape and size. Because each black pearl is highly individual, it is extremely difficult to find pearls of the same quality to form a necklace. A necklace of black pearls is, therefore, valued comparatively higher than those of other pearls.

Like other precious metals, gold is measured by troy weight and grammes. When it is alloyed with other metals, the term carat is used to indicate the amount of gold present, with 24 carats (K) being pure gold and lower ratings indicating proportionally less gold content.

While the price of gold is determined on the open market, a procedure known as Gold Fixing in London provides a twice-daily benchmark figure to the industry.

White gold is an alloy of gold and at least one white metal such as silver or palladium. White gold is typically 18K, 14K or 9K, but can be other carat weights determined by its composition. For example, 18K yellow gold is made by mixing 75% gold (750 parts per thousand) with 25% (250 parts per thousand) of other metals such as copper or zinc. 18K white gold is made by mixing 75% gold with 25% of a white metal such as silver or palladium. As such, while the amount of gold is the same, the alloy is different.

Rhodium plating is used to make white gold look whiter. The natural colour of white gold is actually a light grey colour. But although Rhodium is very white and hard, it will wear away eventually. Therefore, to keep a white gold ring looking its best, it should be rhodium-plated approximately every 12–18 months.

A gemstone is a naturally occurring crystalline form of a mineral, and is desired for its beauty and valued for its rarity.

As there are more than 30 gem varieties, we have highlighted some of the more popular ones here.

For a full list of our gemstones, please click here

The ruby is the red variety of the corundum mineral, which also includes the sapphire. Pure corundum is colourless. As such, it is the slight traces of colour-creating elements such as chrome, iron, titanium or vanadium that are responsible for the ruby’s colour. As one of the hardest minerals on Earth, the ruby is second only to the diamond in its hardness. Only red corundum can be called ruby. Any other colour is known as sapphire.

Colour is everything
Colour is a ruby’s most important feature, with transparency as a secondary consideration. As such, inclusions do not affect the quality of a ruby, unless they decrease the transparency of the stone or are located right in the centre of its table. The cut is essential as only a perfect cut will underline the beauty of this valuable and precious stone appropriately.

Just like the ruby, the sapphire belongs to the corundum group and is the second hardest mineral on Earth. Because of its hardness, a sapphire is easy and simple to care for.

A sapphire can come in different colours, but blue is the most common. Sapphire blue has long been a colour related to anything permanent and reliable. It is for this reason that women in many countries settle on the sapphire for their engagement rings.

Opals shine and sparkle in a continually changing play of colours, which experts describe as “opalising”. Depending on the kind, place of occurrence, and colour of the main body, opals are differentiated as:

• Dark/Black Opal
• White/ Light Opal
• Milk/Crystal Opal
• Boulder Opal
• Opal Matrix
• Yowah Nuts from Queensland, also known as “picture stones“
• Mexican Fire Opal
• Common Opal (lacking the typical play of colours)

In order to best bring out the play of colour in a fine opal, the stones are cut and polished to round or oval cabochons, or any other softly domed shape, depending on the raw material. Only the best qualities of the Fire Opal, with its orange-red fiery shimmer, however, are suited for faceting.

Opal loves to be worn on the skin
Opals can turn brittle due to their water content – which is usually between two and six per cent. When stored in a place that is too dry or exposed to heat over a long period of time, opals will show fissures and the play of colour will become paler. Therefore, opal jewellery should be worn as often as possible so that the gemstone can receive the needed humidity from the air and the skin of its wearer.

This gem is mainly green but is also found in shades of white, grey, black, yellow, orange, and in delicate violet tones. Known to man for some 7,000 years, it was considered an ideal material for weapons and tools in prehistoric times. Even as early as 3,000 B.C., jade was known in China as ‘yu’ or the ‘royal gem’. In the long history of art and culture of the expansive Chinese dynasty, jade has always had a very special significance, roughly comparable with that of gold and diamonds in the West.

What is jade?
‘Jade’ is a generic term for two different gems, nephrite and jadeite. But it was not until the beginning of the 19th century that mineralogists and gemmologists started to differentiate between them as they bear a considerable resemblance to each other in terms of their appearance, hardness and the properties they exhibit when being processed. Although both are tough, as they consist of dense, close-grained, matted aggregates, they differ from one another in their chemical composition and colours. Only in the very finest jade is the colour evenly distributed. Both nephrite and jadeite often have veins, blemishes and streaks running through them, though these may not always be regarded as flaws. On the contrary, some of these patterns are considered particularly valuable.

What distinguishes good jade?
In general, the value of jade is determined according to its:

• Colour
• Colour Intensity
• Vivacity and Texture
• Clarity
• Transparency

Preferences for particular colours vary from region to region and culture to culture. In the US and Europe, emerald green, spinach green and apple green are regarded as particularly valuable. In the Far East, on the other hand, pure white or a fine yellow with a delicate pink undertone is highly esteemed. In the world of jewellery, the fine violet nuances of lavender jade are very popular. It is, however, the rare emerald green of imperial jade that fetches the highest prices.

Fake or poor-quality products or stones that have been coloured or otherwise treated have been offered for sale. To ensure the integrity of your purchase, it is advisable to buy jade only from reputable dealers and jewellers. In recent years, creative jewellery and gemstone producers have come up with some wonderful modern jewellery designs to update the image of jade.