Coloured diamonds

Nightingale can supply an outstanding collection of coloured diamonds loose or set within a bespoke or finished piece of Nightingale jewellery.
Coloured diamonds

Nightingale coloured diamonds

In addition to our comprehensive collection of mined and lab grown diamonds Nightingale can supply an outstanding collection of coloured diamonds loose or set within a bespoke or finished piece of Nightingale jewellery.

What is a coloured diamond?
Coloured diamonds have the same crystalline structure colourless diamonds but are much rarer than colourless ones: approximately 1 in 10,000 diamonds is considered to be a coloured diamond.

What colours are available?
More than 300 diamond colours have been identified in an infinite number of shades. The most popular colours for diamonds are pink, yellow, blue and green. Green diamonds are extremely rare as they contain clustered nitrogen atoms or in some cases no nitrogen atoms because they have been exposed to nuclear radiation during their growth.

How is colour determined?
Colour is the most influential factor in valuing a coloured diamond. Colour is ascertained based on the following attributes:

Hue: Hue refers to the dominant colour of the diamond. It can be affected by the presence of 'tints', which are additional hues within the stone. The hue of a stone with no tints present is described as a pure primary colour, for example, 'a pink diamond'. If a pink diamond has a purple tint, it would be described as 'a purplish-pink diamond'.

Tone: Tone refers to how light or dark a stone appears. This is determined by how much brown, black, grey or white is present.

Saturation: Saturation refers to the intensity of the hue within the stone. The saturation of lightly toned diamonds can range from ‘light’ to ‘intense’ to ‘vivid’ in description. For darker diamonds, descriptions range from ‘dark’ to ‘deep’.

Distribution: Distribution refers to how evenly spread the colour is throughout a diamond.
Professional gemologists assess these variables and produce a natural coloured diamond grading report, which is used to value the natural coloured diamond.

The 4C’s are also assessed on coloured diamonds however, in the GIA grading report the colour aspect is detailed further by describing:

Origin: Describes whether the stone is a natural or treated colour.
Grade: Hue, tone and saturation are all considered when grading colour.
Distribution: how evenly spread the colour is throughout the diamond.

Why should I buy a coloured diamond?
Customers who invest in coloured diamonds value the rarity and prestige of these exquisite stones. Whilst coloured diamonds are significantly more expensive than colourless diamonds their value may increase much quicker year on year. Demand for coloured diamonds is continuously growing, whilst supplies are rapidly falling. Fewer natural coloured diamonds are found every year and as a result prices are rising significantly.

What is the difference between buying coloured and colourless diamonds?
Because of the rarity of fancy diamonds it is hard to find high clarity graded coloured diamonds and colour is more important than cut and the more saturated the colour of the diamond, the less important clarity will be.

How much more expensive are coloured diamonds?
Depending on the availability of these rare stones a 0.73 carat fancy pink diamond would be approximately £22,000 for a fancy light to £65,000 for a fancy vivid. (Prices valid December 2016)

How are coloured diamonds graded?
Coloured diamonds are graded on the ‘fancy scale’ that ranges from fancy light, which is a simple hint of colour through to fancy deep. Fancy deep diamonds are the rarest and most valuable coloured diamonds.

Diamonds are classified following what happened to their structure during the crystallization process. They are divided into two groups: type I and type II, the second one being by far the rarest.

Type I Diamonds
These are diamonds that absorbed a detectable quantity of nitrogen atoms, which absorb blue light.

Type Ia: If the nitrogen atoms are clustered together within the carbon lattice, then the diamond is said to be a Type Ia diamond. Because these diamonds absorb blue light, they can have a pale yellow colour. 98% of diamonds are Type Ia.

Type Ib: If the nitrogen atoms are evenly spread throughout the carbon lattice, then the diamond is said to be a Type Ib diamond. These diamonds absorb green light as well as blue light, and have a darker colour than type Ia diamonds. Less than 0.1% of diamonds belong to Type Ib.

Type II Diamonds
Are diamonds that absorb no, or very few, nitrogen atoms.

Type IIa: These diamonds are considered the "purest of the pure" as they contain minimal amounts of elements. An imperfect carbon lattice will make the diamond absorb some light, which will give it a yellow, brown or even pink or red colour. 1-2% of diamonds belong to Type IIa.

Type IIb: These diamonds contain no nitrogen but they do contain boron, which absorbs red, orange and yellow light. These diamonds usually appear to be blue, although they can also be grey or nearly colourless. A part of naturally blue diamonds belong to Type IIb, which makes up 0.1% of all diamonds.

Further reading


5 styling tips for Montana sapphire engagement rings

The stunning teal coloured sapphires from Montana are fast becoming one of the most popular engagement ring style choices of 2022. 

At Nightingale we love their distinctive aesthetic and their ethical origins and they frequently appear in our ethical engagement rings.

If you'd like to learn more about these beautiful gemstones then read our full guide now! 

Read More

Ethical rubies - Everything you need to know

Rubies are famed for their signature deep red colour and have been treasured by all cultures throughout history.

Often referred to as the ‘King of precious stones’ they make a perfect gemstone for engagement rings due to their beauty, hardness and symbology, often conjuring feelings of passion, love and loyalty.

If you’re looking for an ethical engagement ring with these beautiful gems you’re in the perfect place to learn more. Read on for the full story.

Read More

Emerald engagement rings - A full buying guide

The beautiful green emerald sits alongside diamonds, sapphires and rubies in the ‘Big 4’ of gemstones. 

A favourite of the Egyptian Queen Cleopatra, emeralds have been mined since at least 300BC, leaving their mark on history whilst still being one of the most sought after gems of modern times.

Today we’re going to help you get familiar with these luscious gemstones as well as giving you some practical tips if you’re looking to use them in your engagement ring.

Read More

How to buy ethical diamonds

At Nightingale we’re all about ethical diamonds. And as far as we’re concerned, they should be the minimum standard when making jewellery. 

Unfortunately, that’s not the case. It took a lot of time and effort for us to find sustainable diamond suppliers for our ethical engagement rings and we'd rather you didn’t have to go through the same trouble.

So we’re going to lay out all the knowledge we have to help you find a truly ethical diamond.

Read More

The Valentine's Day engagement ring guide

One of our favourite times of year is nearly upon us. Valentine’s Day!

Being the most popular engagement date of the year, we naturally get a lot of questions from customers. So we thought why not put everything we know into a handy engagement ring guide for Valentine’s Day 2022!

Here’s what we’ll cover...

  • Popular engagement ring styles for 2022
  • Tips for finding the perfect ring
  • Advice on making the most of your budget

Read More

The complete Toi et Moi engagement ring guide

A firm contender for the most romantic style of engagement ring, the symbolism of the Toi et Moi ring (or Moi et Toi as they're also known) is plain for all to see. Two gemstones. One representing you. One representing your soulmate.

This beautiful design style is enjoying a revival which looks to continue well into 2022 and beyond. If you're interested in a toi et moi engagement ring you'll find all the information you need to know right here in our easy guide.

Read More

White gold v Platinum - Which is best for engagement rings?

White gold and platinum can give a similar aesthetic to your engagement ring, but there are some important differences between the two metals which can be important when choosing between them.

Both are very popular choices for engagement rings, so we thought it best to give you a simple guide to help you decide.

Read More

How to get the perfect engagement ring for any budget

Deciding to propose to your partner is a big decision. And along with that decision usually comes a big financial commitment to buy a suitable engagement ring. 

Here's 6 tips to help you get a ring that's perfect for you and your budget.

Read More

Choosing the right metal for your bespoke ring

Choosing the right metal for your bespoke engagement ring is one of the most important choices you can make when creating a ring. The right material sets the overall style of your ring and if done correctly, complements your choice of gemstone and mount.

Read More

The Ethical Diamond Ring Buying Guide - 2022 Edition

It seems like so many industries are making great sustainability strides, but the jewellery trade continues to drag it's heels. Confusing and ineffective 'green' schemes. A lack of transparency in the origins of diamonds and other materials.

It all combines to make buying ethically a minefield, but at Nightingale, we're doing our best to make it as simple and transparent as possible.

So whether you want to buy ethical diamond jewellery from us, or somebody else, this guide will give you the information you need, all the key questions you need to ask and the best possible chance of buying beautiful jewellery from somewhere that is making a positive difference in the world.

Read More

Moissanite v diamonds: Everything you need to know

Curious about moissanite? Having trouble deciding which gemstone to use for your ring? Read on to find out more about the key difference between moissanite and diamonds (both mined and lab grown!)

Read More

Pearl buying guide

Prized and admired for millennia. As the first true gems ever to be used as adornments, the history of pearls in jewellery is nearly as old as the history of civilisation itself.

Read More

Diamond grading certificates explained

A diamond certificate is the evaluation by a third party accredited gemological laboratory of your diamond. In addition to the diamonds carat weight and measurements, a certificate includes grades for the diamonds cut colour and clarity.

Read More

Ring sizing guide

The last thing we at Nightingale want is to supply a ring and at the crucial ‘down on one knee’ moment it turns out to be too large or too small. Nightingale offer one adjustment free in the first three months.

Read More


It is mandatory in Great Britain for precious metals that meet the weight criteria to be assayed and hallmarked (stamped) to indicate the type and fineness of the metal.

Read More

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.

Read More

Lab grown diamonds: Everything you need to know

Wondering what exactly a lab grown diamond is and why they're a perfect ethical alternative to mined diamonds? Find out here...

Read More