About Precious Colour Stone

Diamond, Ruby, Sapphire and Emerald are referred to as the four most precious stones in the world. They are highly valuable for their beauty and rarity. They have been desirable since ancient times and have always been a royal favourite.

For anyone who is interested in buying a special and impressive engagement ring with ruby, sapphire or emerald, here are some facts and features and our buying guide of these beauties.


Ruby can command the highest per-carat price of any coloured stone. This makes ruby one of the most important gems in the coloured stone market. Ruby and Sapphire both belong to the corundum mineral species. Chromium is the trace element for ruby’s red, which ranges from an orangy red to a purplish red.

Being the colour of love and passion, ruby is often regarded as the stone for love. It is also associated with power and desire. Early cultures treasured rubies for their similarity to the redness of the blood that flowed through their veins, and believed that rubies held the power of life.

Ruby as been called the most precious of the 12 stones created by God. It is one of the most sought-after gems of European royalty and the upper class. Desire for ruby is just as great today as it always has been. As a symbol of love and passion, ruby makes an ideal romantic gift.

Ruby is the birthstone for July and the gem for the 15th and 40th anniversaries.

Ruby Buying Guide

Colour is the most important quality factor for ruby. The finest ruby has a pure, vibrant red to slightly purplish red colour. The most demanding colour today is referred to “Pigeon’s Blood”, which has a vivid colour saturation, like the blood of a pigeon.

Rubies are expected to have at least some inclusion because inclusion-free rubies are extremely rare. Ruby value depends on how visible the inclusions are.

If all factors are equal, rubies mined in Burma are usually more desirable than from other places.

Rubies that are not treated command far higher prices than the treated ones. Most rubies on the market nowadays are heat-treated and are widely accepted. Glass filling is another common treatment but is much less durable and makes them a lot less desired.

Care and Clean for Ruby

Ruby is extremely hard and durable, which makes it good to wear everyday. But it is important to avoid rubbing ruby against other gemstone, such as diamond and sapphire. It can also damage other softer stones such as emerald and topaz.

Warm, soapy water is usually used for cleaning ruby. Ultrasonic and steam cleaners are only safe for untreated rubies.


Sapphire comes from the same corundum family as ruby. In fact, the name “sapphire” applies to any corundum that is not red and doesn’t qualify as ruby. Most people think Sapphire to be blue, but it actually comes in a rainbow of colours, such as violet, green, yellow, orange, pink, purple, etc. Blue sapphire is straightly called “sapphire”, and all other coloured sapphire are called fancy-sapphire, and are referred to by adding the colour before “sapphire”, such as “pink sapphire”, “yellow sapphire”, etc.

Sapphire is the birthstone for September. It symbolizes sincerity, truth, faithfulness and nobility. For centuries, sapphire has adorned royalty. The ancient Greece and Rome believes that sapphire protected their owners from harm and envy. In addition to being the September birthstone, sapphire is also the gem commemorating the 5th and 45th wedding anniversaries.

The most well known sapphire in the recent years is the 12ct blue sapphire ring first worn by Princess Diana and now by Kate Middleton, the Duchess of Cambridge. Another famous sapphire was the 62.02ct Rockefeller Sapphire that was acquired in 1934 by John D. Rockefeller Jr. Other most famous historical sapphires include the 423ct Logan Blue Sapphire, the 563ct Star of India and the 478ct Queen Marie of Romania’s Sapphire.

Sapphire Buying Guide

When it comes to buying sapphire, colour is the most important quality factor. The most highly valued blue sapphires are velvety blue to violetish blue, in medium to medium dark tones. The saturation should be as strong as possible without darkening the colour or compromising brightness.

The most popular colour of sapphire in the market today is referred to as “royal blue”, which probably came from the British royal story of Princess Diana and her sapphire engagement ring. Probably the most demanding colour of the September birthstone is the velvety “cornflower” blue from Kashmir. Since the 1880s, “cornflower” sapphire has been considered the finest sapphire and has become a collector’s favourite.

Clarity is another factor to consider when buying sapphire. Sapphires often have some inclusions. Clarity refers to the lack of inclusion in a stone. Sapphires with extremely high clarity are rare and very valuable.

Cut is one of the most important factors in appearance. Sapphires are usually cut to achieve the best overall colour, maintain the best proportions, and retain the most weight possible. Sapphires are commonly seen in oval cut, pear cut, cushion cut and emerald cut.

Location is another important factor that affect sapphire’s value. Kashmir, Myanmar (formerly Burma) and Sri Lanka are three historically important sources for sapphire. Kashmir sapphire has a very high reputation as one of the world’s most coveted gems and is very rare on the market. Burmess sapphire can possess a rich, intense blue hue, which has made it particularly prized. Today, Sri Lanka is the steadies and largest producer of sapphire. It is also the source for the very rare pink-orange sapphire known as padparadscha sapphire. Sapphires from the above three locations are more in demand and usually particularly prized.

Significant quantities of the sapphire have also been found in Australia, Thailand, Cambodia, Madagascar and the United States (Montana), among other countries in Asia and Africa.

Care and Clean for Sapphire

Sapphire is very hard, ranking 9 on the Mohs scale. It has excellent toughness and no cleavage which makes it a perfect choice for rings and for daily wear. Nowadays, most sapphire are treated to improve their colour and clarity. Heat treatment is the most common method and the results are permanent, so it is well accepted in the trade. Less common treatment such as lattice diffusion, fracture filling and dyeing will require special care. Some fracture-filled and dyed sapphire can be damaged by even mild acids such as lemon juice or detergent.

Warm, soapy water is a safe choice for cleaning sapphire. Ultrasonic and steam cleaners are usually safe for untreated sapphire.


Considered the gem of spring, Emerald’s beautiful blue green hue has entranced mankind for almost 3 billion years! Emerald is considered part of the “Precious Four” gemstones including Ruby, Sapphire and Diamond. Coming from the Beryl family as Aquamarine, Emerald is a relatively hard gemstone (rated 7.5-8 on the Mohs scale) having a fairly good toughness. However, this gem requires more care when wearing than sapphire or ruby.

Emerald is May’s birthstone, and also the gem of the 20th and 35th wedding anniversaries.

Emerald Buying Guide

Colour is the most important quality factor when it comes to buying emerald. The most desirable emerald colours are bluish green to pure green, with vivid colour saturation and tone that is not too dark. The most-prized emeralds are highly transparent with evenly distributed colour and no eye-visible colour zoning.

Natural emerald generally has inclusions that are visible to the unaided eye. Eye-clean natural emeralds are especially valuable because they are so rare. A well-priced gem that appears flawless in clarity is considered suspect as it is likely to be a synthetic or simulant. Most emeralds are treated with oil, resin, and/or polymers to reduce the appearance of inclusion and surface reaching breaks.

Emerald cut – a square or rectangular step cut is the most popular cut for emerald. This cut maximizes the shape and weight of the natural emerald and best show its beauty.

Are emeralds from Columbia worth more? While Columbia is considered the premier source for fine quality emeralds, every mine produces a wide range of quality.

Care and Clean for Emerald

Emerald has a fair to good toughness and requires more care in wearing than ruby or sapphire. Heat can damage emeralds and extensive light and chemicals can cause the oil, resins, and polymers used to fill surface-reaching fractures to alter I appearance or deteriorate. So it is important that you remove your emerald jewelry before doing any cooking or cleaning. It is also not recommended to wear it to the beach.

To clean emerald jewelry, use warm, soapy water coupled with gentle scrubbing. Do not clean with ultrasonically or with steam.