Coloured Stone Guide

Coloured gemstones have been admired and treasured for their beauty, rarity, and uniqueness for centuries. From the fiery red of rubies to the cool blue of sapphires and the lush green of emeralds, the vibrant hues of these gemstones have captivated the imagination of people around the world. In this comprehensive guide, we’ll provide an introduction to coloured gemstones, their characteristics, and what to look for when purchasing these dazzling jewels.

An Intro to Gemstone Colour

The colour of a gemstone is its most defining feature and contributes significantly to its value. In fact, around 60 percent of a gemstone’s value is based on its colour alone. Understanding the colour of gemstones involves examining three factors: hue, tone, and saturation.

The Hue of a Gemstone

Hue refers to the colour itself, such as red for rubies, blue for sapphires, or green for emeralds. Gemstones often have a primary and a secondary hue. However, when evaluating a gemstone’s colour, experts often search for stones that are as free from secondary colours as possible. Generally, the most valuable gemstones exhibit a pure colour and only slight hues of others. 

Exceptions include opals, which are unique gemstones that increase in value when there are more visible colours throughout.

The Tone of a Gemstone

Tone refers to the depth of a gemstone’s colour, ranging from light to dark. Experts use terms like light, medium-light, medium, medium-dark, and dark to describe a gemstone’s tone. Evaluating the value of a gemstone based on its tone involves holding it under a table or away from direct light. This technique allows you to more easily determine the tone of a gemstone since a brighter stone will still have life and brilliance even when light isn’t directly shining on it.

The Saturation of a Gemstone

Saturation refers to the intensity of a gemstone’s colour, ranging from light to strong to vivid. The more vivid the gemstone, the more valuable it is. For example, the value of an emerald gemstone largely depends on how green the stone is, and the price may drop significantly when the colour begins to approach a more “mossy” shade of green.

What to Look for When Buying a Gemstone

When purchasing a coloured gemstone, consider the following characteristics:

1. Colour: Gemstone colour is perhaps its most important quality. While the most valuable stones exhibit pure primary colours, personal preferences should also play a significant role in your decision. Choose a gemstone that appeals to your taste and style.
2. Brilliance: A gemstone’s brilliance refers to how bright it looks when you and the gemstone are stationary. Brilliance is the result of how much light is reflected by the stone and the contrast pattern dictated by the cut.
3. Scintillation: A combination of brilliance and scintillation gives a gemstone its sparkle or liveliness. Determining how scintillating a gemstone is requires either the gemstone or the viewer being in motion.

Popular Coloured Gemstones

Rubies

Rubies are highly sought-after gemstones known for their vibrant red hue. They symbolize love, passion, and courage. The most valuable rubies are those with a strong, pure red hue with minimal secondary colours.

Sapphires

Sapphires are prized for their rich blue colour and have long been associated with royalty and wisdom. The finest sapphires exhibit a deep, vivid blue hue with minimal secondary colours. In addition to blue sapphires, these gemstones also come in various colours, such as yellow, pink, and even colourless, known as fancy sapphires.

Emeralds

Emeralds are known for their vibrant green colour and are often associated with rebirth, growth, and prosperity. The most valuable emeralds possess a vivid, intense green hue with minimal secondary colours and even saturation.

Aquamarine

Aquamarine is a gemstone known for its serene blue to greenish-blue hues, reminiscent of the ocean. These gemstones are believed to symbolize tranquillity, peace, and protection. The most valuable aquamarines exhibit a deep, pure blue hue with minimal secondary colours.

Topaz

Topaz comes in a variety of colours, including blue, yellow, pink, and even colourless. The most valuable topaz gemstones are those with vivid, intense hues and minimal secondary colours. Blue topaz, in particular, is a popular choice for its calming hue and affordable price point.

Garnet

Garnet is a versatile gemstone that comes in various colours, including red, orange, yellow, green, and even colour-changing varieties. The most valuable garnets exhibit vivid hues and even saturation. Red garnets, such as pyrope and almandine, are some of the most popular varieties.

Peridot

Peridot is known for its bright, vibrant green hue, often with a hint of yellow. It is believed to symbolize abundance, prosperity, and growth. The most valuable peridots possess a rich, even green hue with minimal secondary colours.

Amethyst

Amethyst is a popular and affordable gemstone known for its stunning purple hue. It is often associated with spirituality, creativity, and balance. The most valuable amethysts exhibit deep, vivid purple hues with minimal secondary colours.

Tourmaline

Tourmaline is a unique gemstone that comes in various colours, including green, pink, blue, and even bi-coloured or multi-coloured varieties. The most valuable tourmalines exhibit strong, vivid hues and even saturation. Some of the most sought-after varieties include Paraiba tourmaline and rubellite.

Gemstone Cut, Clarity, Size, and Enhancements

In addition to colour, other factors contribute to the value and appeal of coloured gemstones. These include:

1. Gemstone Cut: The cut of a gemstone affects its brilliance, scintillation, and overall appearance. A well-cut gemstone maximizes light reflection and enhances the stone’s inherent beauty.
2. Gemstone Clarity: Clarity refers to the presence of inclusions or blemishes in a gemstone. While some inclusions can negatively impact a gemstone’s value, others might contribute to its uniqueness and charm.
3. Gemstone Size: The size of a gemstone, usually measured in carats, can influence its value. Larger gemstones are generally rarer and more valuable than smaller ones, assuming equal quality in other factors.
4. Gemstone Enhancements: Gemstones are sometimes treated to enhance their appearance, such as through heating, irradiation, or oiling. While enhancements can improve a gemstone’s colour or clarity, they might also affect its value and require special care.

Conclusion

Coloured gemstones are a captivating and diverse world of beauty, rarity, and symbolism. When selecting a coloured gemstone, consider factors such as hue, tone, saturation, cut, clarity, size, and any enhancements. Ultimately, choose a gemstone that resonates with your personal style and preferences. 

With this compact guide, you’ll be well-equipped to navigate the world of coloured gemstones and find the perfect piece to treasure for years to come.

At WRB, our passion for coloured gemstones and dedication to quality ensures that we offer a stunning selection of exquisite gems, allowing you to discover and appreciate the unique beauty of each stone while making a wise investment in a piece you’ll cherish for a lifetime.