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Ruby Guide

Buying tips, facts & history



our source

Our Source

mineral class

Mineral class


9 Mohs Scale

birthstone month

Birthstone month

wedding anniversaries

Wedding anniversaries
15th and 40th

ruby facts

Hard Facts

“Ruby” comes from the Latin word “ruber”, meaning red. Rubies consist of a mineral called corundum. Rubies can vary from pink to a deep red colour (other colour varieties of corundum crystals are called sapphires).

It is the third hardest mineral substance in the world, only diamonds and moissanites are tougher. On the Mohs scale of hardness, ruby registers a 9.

where on earth?

Where on Earth?

We choose to buy our rubies from Thailand.

Not only are Thai rubies of an excellent quality, but also conflict-free and ethically mined.

Rough rubies can look quite dull when they first come out of the ground. A highly experienced eye is therefore needed to pick out the best quality stones and shape them into beautiful gems.

Thailand has an ages old tradition in gem mining, vending and cutting, guaranteeing a far superior grade of rubies compared to other sources.

july birthstone

Birthstone and Anniversary

Ruby is the birthstone for July.

It is traditionally gifted on 40th “Ruby” anniversaries, but in modern times has also become popular for 15th wedding anniversaries. Red ruby jewellery is said to remind us of love and passion, making it an extremely popular gift for all romantic occasions.

ruby buying guide

Buying Guide

How to assess a Ruby’s quality and value?

Rubies are so sought after that they often have the highest per-carat price of all coloured gemstones.

When assessing rubies, our gemmological expert first looks at colour. A pure red hue is the most important quality of a good ruby. Unlike with sapphires or emeralds, clarity is considered secondary.

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A superlative ruby has a strong saturation of colour that varies from bright red to purplish red. Historically, “pigeon’s blood red” has been used to describe the desirable vividness of colour in rubies. If a ruby is too dark, it loses sparkle, if it’s too light, it will be classed as a pink sapphire.

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Rubies of an excellent commercial quality can be found in a variety of sizes. However, the bigger a ruby gets the more it costs per carat. For example, a 5-carat ruby will usually cost around ten times more than a 1-carat ruby. This is often because bigger crystals of a high quality are harder to come by, or perhaps because the cutter needed to lose greater quantities of the original, rough stone to create a workable shape.

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Our gem expert advises buyers to expect some natural inclusions in ruby jewellery. This is indeed the opinion held by everybody in the gem industry. Perfectly clear rubies are so rare they fetch prices only attainable by collectors. Commercial ruby jewellery will therefore always have slight natural inclusions.

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Rough rubies are extremely expensive. That’s why gem cutters, when cutting a ruby into shape, try to save as much of the original stone as possible. This often determines the final form of a ruby. It is also the reason why most rubies used in jewellery are oval of cushion cut. Other shapes, such as the pear, marquise or round-brilliant are available, but they tend to be reserved for bigger, more expensive stones.

natural or treated rubies

Natural or Treated?

While rubies can be heat-treated or fracture-filled to intensify colour or hide inclusions, our jeweller recommends only buying gems that are natural. Typically, rubies used in jewellery will almost certainly appear to have tiny lines. You shouldn’t regard them as imperfections – these small, barely visible marks are a sign that your ruby is authentic.

ruby care

Care and Cleaning

Ruby jewellery can be cleaned at home or be taken to a jeweller for a professional polish. At home, the easiest and safest way is to wash your rubies in a bowl filled with warm water and a drop of mild soap, using an old toothbrush to remove any insistent dirt. Remember to scrub very gently so you don’t loosen any stones. Alternatively, you can take your rubies to a local jeweller where they’ll give them an ultrasonic clean.

modern history

Modern History

Rubies today symbolise love and enchantment. In The Wizard of Oz, we all remember how Dorothy’s magical ruby slippers transported her back home to Kansas.

Elizabeth Taylor, Victoria Beckham and Jessica Simpson are some of the famous women who’ve loved to show off rubies. Like red roses and hearts, rubies are considered a quintessentially romantic Valentine’s Day gift.

famous rubies

Famous Rubies

When The Dukes of Hazzard actress Jessica Simpson got engaged to Eric Johnson in summer 2014, the beautiful and unique ruby ring he gave her made big headlines. It was of course symbolic of their engagement, but he also wanted it to commemorate her July birthday. The ring features a stunning 5-carat ruby shouldered by two diamonds, set in a yellow gold band. Celebrity magazines have estimated its cost at around £350,000.

legend and myth

Legend & Lore

Rubies are possibly the most significant of all coloured gems in history. They are mentioned numerous times in ancient Sanskrit scriptures as the “king of gemstones” and the Bible associates them with beauty and wisdom.

The Hindus believed they could achieve rebirth as royalty if they sacrificed rubies to Krishna. In China the rank of a Mandarin was shown by the colour-tone of the ruby on his ring.