July's birthstone: Ruby, 'king of the gemstones'

Those fortunate enough to be born in the month of July have ruby as their birthstone. The red form of corundum, ruby’s name comes from the Latin ruber meaning red. The ancient Indians called ruby ratnaraja, ‘king of the gemstones’, for its rarity, hardness, and beauty.

Ruby’s colour

Ruby’s famous colour is derived from trace amounts of chromium replacing aluminium in the crystal structure. Because the chromium also impedes crystal growth, stones larger than ten carats are extremely unusual and correspondingly expensive, helping ruby to achieve its long-held association with wealth. Indeed, since biblical times rubies have been alluded to as an expression of value, with the Bible stating that learning, wisdom and a capable, intelligent and virtuous woman are more precious than ruby. The modern novelist Salman Rushdie titled one of his short stories ‘Good advice is rarer than rubies’.

Ruby’s meaning

A Ruby, Emerald, Sapphire, and Diamond Bracelet

The chromium that causes the red colour is also responsible for one of ruby’s more intriguing qualities: many fluoresce under long-wave ultraviolet light and can seem to glow in bright sunlight. Historically, this lovely trait has added a layer of mysticism to rubies and led to the idea that rubies were created by fire and held within them an inextinguishable fire. There have also been tales of rubies that darken with ill health or glow to signify impending danger. Certainly, it is something to be aware of when buying rubies: a beautiful gem bought under hot tropical sun can seem a little dull on a wet day in a cooler northern climate.

Whilst rubies vary from a pinkish red to a deep brownish red, the finest rubies are blood red. It’s no doubt due to this that ruby has been credited with many of the symbolic meanings associated with blood such as life, passion and health. Burmese warriors wore it as a protective amulet in battle that was particularly effective if worn under the skin so as to merge with their own blood.

Indian jewellery has traditionally used ruby to symbolise youthful energy and vitality, whilst in medieval Europe rubies were thought to be a useful remedy for illnesses relating to the blood such as swelling, haemorrhages and anaemia, as well as to stimulate the kidney and reproductive organs.

A symbol of love

The red of rubies also links them irrevocably with love and romance, and they have been used to demonstrate devotion since time immemorial. The traditional symbol of love, engagement rings have been set with rubies as far back as Roman times and have more recently been chosen by Princess Margaret and Mark Zuckerberg. Romantic rubies are also traditionally gifted to celebrate 40 years of marriage on a couple’s ruby wedding anniversary.

An antique Victorian Ruby and Diamond Ring in 18 carat Gold

A Ruby and Diamond Ring in Yellow Gold

However, perhaps one of the most iconic examples of rubies as a symbol of love is the moment Mike Todd presented Elizabeth Taylor with a diamond and ruby parure as they were by the pool in the south of France. Caught on a home movie, the jewels glow and sparkle in the Mediterranean sun as does the delight in Elizabeth’s face. She later described it as “a perfect summer day and a day of perfect love”.