When one hears the name Garnet, the first thing that springs to mind is the wonderful deep-red gemstone often found in antique jewellery. This thought is absolutely correct, however, few people are aware of the variety of colours that a Garnet can be found in. Red is still the most abundant of finds but colours throughout the colour spectrum are available – from radiant orange through to green garnets, but never blue. Garnets of all colours have become valuable; especially the star garnets and the stones which change colour in different light conditions. The word Garnet comes from the Latin granatus which is possibly referring to the pomegranate (Punica granatum) because of the similarity of garnets to the fruits seeds.

The Garnet is a relatively hard stone receiving a rating of 7.0 to 7.5 on the Mohs Hardness Scale. This, and the fact that it is an easy stone to work with, explains its popularity as a gemstone suitable for jewellery making. They have a high refractive index causing them to exude a great brilliance, but they do not like being knocked around or being subjected to improper heat treatment.

The distinctive purple shade of amethyst has made it a highly sought-after gem with a rich and ancient history.

Amethyst is the most prized of all gems in the quartz group. Amethyst is dichroic, showing a bluish or reddish purple tinge when viewed from different angles, and the name is derived from the Greek word “amethystos” which expresses their believe that the gem could ward off intoxication and have a soothing, relaxing effect.

Amethyst, capable of intoxicating beauty, was fashioned into ornate pieces of jewellery and used it to decorate swords, shields and amulets since early civilisation. It was also chosen to adorn the crowns of kings and queens such as the huge round amethyst set in the British Royal Sceptre, and another in the Sovereign Orb. Within the Christian Church, high officials have long favoured amethyst. Zambia, Namibia and Madagascar produce amethyst that is considered the worlds finest.

Amethyst is the birthstone for February and signifies sincerity. It is also given as a gift to mark the first wedding anniversary. Amethyst aligns with the Star Signs Aquarius and Pisces.

The Diamond is the hardest natural element and the name is derived from the Greek adamas – meaning invincible. They have been treasured as gemstones since their use as Religious Icons in ancient India and have been used industrially as engraving tools. Diamonds are judged by “the four c’s” – Carat, Clarity, Colour and Cut. The first diamond discoveries were in India and there is proof of mining in India as early as the 1660s at Kollur, near Golconda. The earliest reports of any discoveries in South Africa came through as early as 1750 from Missionaries in the Cape of Good Hope. Roughly 49% of diamonds originate from southern and central Africa, but other sources have been found in Canada, India, Russia, Brazil and Australia.

With the release of the Leonardo DiCaprio movie last year entitled “Blood Diamond” a new focus on diamonds and their origin has become prevalent. The mining and distribution of natural diamonds are subjects of frequent controversy such as with concerns over the sale of conflict/blood diamonds. De Beers monopoly on the world market’s supply and pricing has come under the spotlight in recent years.

Emeralds have the most beautiful, intense and radiant green possible and have become equally as valuable as diamonds, sometimes even surpassing them in value. The name is derived from the Greek “smaragdos” via the French “esmeralde” which simply means green gemstone. The best emeralds hail from South America, where the Incas and Aztecs held it as a holy gemstone. The oldest known finds were near The Red Sea in Egypt and from as far back as 3000BC Egyptian pharaohs exploited mines in the area. These became known as Cleopatra’s Mines. They exhausted these resources until emeralds were rediscovered in the early 19th century.

Emeralds all have some inclusions to a degree and are a variety of the mineral beryl. On the Mohs Hardness Scale, they score between 7.5 – 8.0, which is fairly hard, but due to the fractures and inclusions, its toughness is classified as generally poor. They come in many shades of green and bluish green and vary quite vastly in terms of clarity. Clear stones with dark, vibrant colour command the highest prices. Most emeralds are oiled in order to improve their clarity. This is a common trade practice as long as green tinted oil is not used. This does lead to a few warnings to Emerald Owners – Due to the stones’ brittleness and oil enhancement, emeralds cannot be cleaned in an ultrasonic bath. This would remove the surface pores of the stone leaving it with a matt appearance. Please remove your emerald rings if you put your hands into water containing a cleansing agent. You have been warned.

Strictly speaking the Pearl is not really a gemstone, but has become a valuable part of jewellery making for over 6000 years. As far back as 2500BC there was substantial trade in pearls in China. Known as The Queen of Gems throughout history, strands of natural pearls were exclusively worn by the incredibly rich and commanded values much higher than other gemstones. Nobody is certain of the discovery of the pearl, although it is believed that off the coast of India, fishermen discovered them while eating oysters. Regardless of its discovery the pearl has been the centre of historic events from the famous crushing and drinking of a pearl earring by Cleopatra to win a bet with Marc Anthony through to many religious references in both the Koran and the Bible. The principal oyster beds lay in the Persian Gulf, along the coasts of India and Ceylon (now Sri Lanka), and in the Red Sea. Chinese pearls came mainly from freshwater rivers and ponds, whereas Japanese pearls were found near the coast in salt water. Nearly all the pearls in commerce originated from those few sources. As Europe raced to capitalize on what Columbus had stumbled upon, the major powers of the day concentrated on spheres of influence. Spain focused its efforts in Central and South America and the Caribbean. Along both the Atlantic and Pacific coasts of Central America, the Spanish forced slaves to dive for pearls. The English colonizers along North America's Atlantic coast and French explorers to the north and west, all found native Americans wearing pearls, and they discovered freshwater pearls in the Ohio, Mississippi, and Tennessee River basins. So many gems were exported to Europe that the New World quickly gained the appellation "Land of Pearls."

If you close your eyes and think of the word Ruby, instantaneously you see the colour red – a vibrant colour which evokes thoughts of love, passion and power. The ruby is known, in some circles, to be the undisputed ruler of the gemstone world. In fact the Sanskrit word for ruby is ‘ratnaraj’ which means ‘king of the gemstones’. India was initially regarded as the country of origin for the ruby, and through literature over two thousand years, it has been heralded and held in extremely high honour. It is not only its radiant colour and brilliance that make it so valuable, but the fact that it is an extremely hard stone. The Mohs Scale of Hardness puts the ruby at 9.0 – which means only diamond is harder.

The ruby is essentially a variety of corundum, with its colour being caused by chromium. Other coloured corundum stones can be classified as Sapphires, while only red corundum may be called a ruby. Its name is derived from the Latin word for red – ruber. Chrome gives the ruby its phenomenal colour, but also was responsible for causing a multitude of fissures and cracks inside the crystals. This is why very few large stones with very few inclusions are very rare. The value of rubies with hardly any inclusions is enormous and prices have even surpassed those of diamonds at auctions. The highest recorded price at an auction was $5,860,000 for a 38.12 carat cabochon-cut ruby in 2006.

The Peridot is one of only a few gemstones that come in only one colour – the vivid green with hints of gold. It is a very old stone and can be traced back to Ancient Egypt, where it was used in jewellery from as early as 2000BC. In Egypt they were discovered in a small volcanic island in the Red Sea, and then this source was re-discovered around 1900. Since then, this source has been exhausted. More recently, large deposits were discovered in the Kashmir region. These stones have revived the image of the Peridot as they are fantastic in colour and transparency. This was welcomed as before this find, they were known as “poor man’s emeralds”

The rich, green colour with the gold tinge is caused by very fine traces of iron. The intensity of the colour depends on the amount of iron present. It can vary from shades of yellowish green to a brownish green. It is not a hard stone, measuring 6.5 – 7.0 on the Mohs scale, but it is fairly robust and is easy to take care of.

When someone mentions sapphires, you immediately think of the colour blue – a sparkling alive colour. In the earlier days, some people believed the sky was an enormous sapphire in which the earth was embedded. The sapphire comes in all shades of blue from the light sky blue to the deep blue of an evening sky and, surprisingly to many people, in a number of other colours ranging from pink right through to black. Sapphires are the non-red variety of corundum, a mineral which consists of pure aluminium oxide. When traces of other minerals such as iron or chromium are found, the colour of the sapphire is determined. The coloured sapphires are referred to as fancy sapphires or fancies. The Mohs scale of Hardness rates the sapphire at 9, just below the hardest mineral on earth, the diamond. This makes its upkeep very simple. This fact and its truly magnetic colours mean it is one of the most sought=after gemstones for jewellery, particularly recently when coloured stones have become very fashionable.

The sapphire has more surprises in store. There is an orange variety with a fine pink undertone which is called “padparadja” meaning lotus flower. Another beautiful find amongst sapphires is the star sapphire, which are half-dome cut with a star like effect which uses the light to almost glide across the surface of the stone when moved. These stones are incredibly rare and valuable. Sapphires are mined all over the world, particularly in India, Sri Lanka, Australia, Brazil and Africa. Depending on where the sapphire is mined, determines some of its value. Kashmir Sapphires found in 1880 after a landslide 16,000ft above sea level have become incredibly valuable, due to their scarcity and the pure, intense blue colour which has a subtle violet undertone. It also has a silky shine to the stone which does not change in artificial light. Burmese Sapphires are also valuable and range in colours from royal blue to a deep cornflower blue. In modern times most of the sapphires originate in Australia but do not match the quality or colour of the Kashmir, Burmese or Sri Lankan stones.

Opals are fascinating in that they hold such mystery in their appearance; they change with the angle of light to reveal spectrums of colour you find in elements of nature, such as fire and lightning, the colours of a rainbow and the shine of the bluest seas. This continual change of colour is called “opalising”. The word opal comes from the Greek opallios and the Latin opalus, which are from the same root as Sanskrit upala which means stone. Opal is a mineraloid gel which is deposited at a low temperature and occurs in the fissures of almost any kind of rock. Australia is the main producer of opals with almost 95% of all fine opals originating in the dry outback regions. Mexico makes up the other 5%.

Opals variations are unlimited and are dependant on their kind and location of origin as well as the colour of the main body of the stone. They can be Dark or Black Opal, White or Light Opal, Milk or Crystal Opal, Yowah Nuts (also known as picture stones) and the valuable Fire and Mexican Opal. Fire opals are translucent to semi-opaque and range from yellow through bright orange to almost red. The question people have been asking for centuries is how does the opal seem to change colour? In the 1960’s Australian scientists analysed Opals with an electron microscope. It was discovered that small spheres of silica gel caused interference and therefore refraction occurs, resulting in the play of colour.

The Citrine is a bit of a confused stone – it is falsely linked to the Topaz, when it bears very little similarity. The Citrine can be known as Gold Topaz, or Madeira or Spanish Topaz and some Citrines can be of a similar colour to some Topaz. They are part of the large quartz family, which produces every spectrum of colour imaginable and at affordable prices. Its name is derived from the colour – the yellow of the lemon, although the sought after varieties have a clear, radiant yellow to brownish red. As with all quartz stones, the Citrine is a relatively hard stone with Mohs Scale classifying it at 7.0, making it very insensitive to scratches.

There are not many affordable yellow stones which cover the number of colours like Citrine does. Yellow diamonds are expensive, and tourmaline might be too green. These are some of the reasons that the Citrine is gaining even more popularity with the jewellery buying public and ofcourse coloured stones are very fashionable at the moment. It is extremely rare but yellow does in fact occur in quartz in Nature. It has been found in Spain, Scotland, France and Hungary. The Citrine might not have become popular, if it had not been discovered that amethysts and smoky quartzes can be rendered yellow through intense heating. Now, some 200 years later, this heating application is more often than not applied and only a trained eye can recognize the signs of heat treatment.

Tanzanite is an extraordinary gemstone. It occurs in only one place worldwide. Its blue, surrounded by a fine hint of purple, is a wonderful colour. Thanks to its unusual aura and the help of New York Jeweller’s Tiffany & Co, it has rapidly become one of the most coveted gemstones in the world.

It is named after the East African state of Tanzania, the only place in the world where it has been found. On its discovery in 1967, it was enthusiastically celebrated by the specialists as the ‘gemstone of the 20th century’. They held their breath in excitement as they caught sight of the first deep-blue crystals which had been found in the Merelani Hills near Arusha in the north of Tanzania. Millions of years ago, metamorphic schists, gneisses and quartzites formed impressive, flat topped inselbergs on a vast plain in the shadow of Mount Kilimanjaro. The precious crystals grew in deposits on the inside of these elevations. For a long time they were hidden from the eye of Man, until one day some passing Masai shepherds noticed some sparkling crystals lying in the sun and took them along with them.