Jewellery Guide: Collecting Coloured Gemstones

Lara Mansour   |   19 - 05 - 2018


Are diamonds still a girl’s best friend? It may surprise you that right up until the early twentieth century around 50% of engagement rings featured coloured gems and 50% diamonds. This only changed with the intervention of De Beers, who sought to dominate the diamond market by promoting it on a vast scale around the world. They were so successful in achieving this that by the end of the century diamonds accounted for more than 95% of the market. In the twenty-first century we are now seeing this trend reverse and the coloured gem market share expand. Gemfields, often referred to as the ‘De Beers’ of coloured gems, have been an important factor in this shift. Gemfields purchased the 175-year-old Fabergé brand in 2012 for $142 million and they have subsequently launched a bedazzling array of coloured gem engagement rings and jewellery.


The launch ties in with a growing trend for women to veer away from generic white diamond engagement rings, with coloured stones becoming a more common choice among modern brides. Diamonds may be deemed the most valuable gem, but beyond the traditional trio of rubies, emeralds, and sapphires, we are witnessing a rainbow revolution in which previously overlooked stones are now in the limelight.



Although it is true to say the coloured stone market is predominantly centred upon this trio, some more exotic coloured gems are starting to make more of an impact. Beautiful Paraiba tourmalines are becoming increasingly popular since they were discovered in the 1980s in the Brazilian region that gave the stone its name, as are green sapphire, spinel, morganite, amethyst, alexandrite, pink sapphire, golden beryl and many more. The range of hues and colours opened up by this ever-expanding spectrum of gemstones allows designers and craftspeople to create more individual designs. There are also interesting financial incentives for purchasing coloured gemstone engagement rings, as their price point is, in many cases, below that of diamonds. Having said this it is however important to note that some high end Colombian emeralds, such as Burmese rubies and Kashmir sapphires, can fetch many tens of thousands of dollars per carat, often placing them at a substantial premium to many diamonds. Another key advantage that coloured gems possess over diamonds lies in the density of the stones. Diamonds are to be found at 10 on the 1-10 Mohs scale of mineral hardness and are consequently up to 30% denser than emeralds which are at 7.5, resulting in the physical dimensions of an emerald being significantly larger per carat.



Aside from the increased individuality and more accessible price point, there are more practical reasons for coloured stones, such as the vast array of options in terms of cut, colour, and quality, something which Bulgari took advantage of between the 50s and 60s when they were creating extraordinary floral brooches. They started their own style at this stage, using gems for their chromatic effects and daring combinations. This allows for greater flexibility and experimentation, but as with all commodities, increasing demand coupled with diminishing supply will create the most profound price increases. Alongside the increase in demand, there are other factors which are causing these increases, including certification which has had an impact on the gem market in recent years. As buyers of loose stones and jewellery become more savvy in the internet age, they are demanding gems with greater emphasis on the value of the ‘five-C’s’, cut, colour, clarity, carat, and certification. This more discerning consumer buying pattern is driving up the value of certified high-quality stones at a much faster pace, placing greater pressure on supply.



Fancy or Vivid, Know Your Terminology

Coloured diamonds come with their own specific colour categories. A blue diamond, for example, could be classified as Faint Blue, Very Light Blue, Fancy Light Blue, Fancy Blue, Fancy Intense Blue, Fancy Dark Blue, Fancy Deep Blue or Fancy Vivid Blue. The same principle of categorisation applies to coloured diamonds of virtually all hues.

Word Order is Important

Coloured diamonds aren’t always a single colour. You may sometimes see a diamond described as Vivid Orange Yellow or Vivid Yellow Orange. The key here is to look at the last word, which will be the principal and dominant colour.

How Valuable are Different Colours

The rarest of the rare is a red diamond, there aren’t many, and they’re generally not very big. It would be exceptionally unusual to find a red diamond above 2 carats.

What Make’s a Perfect Coloured Stone

When it comes to emeralds, the most coveted are a darkish green. However, it’s important the stone isn’t too dark, as the highest-quality emeralds combine good colour with clarity. The same applies to rubies and sapphires, and you should look for stones with an appealing colour, good clarity, and attractive proportions. A small percentage of the top rubies have a colour referred to as ‘pigeon’s blood, a dark red which must not be too dark. Aim for a rich, warm burgundy that makes you joyful when you look at it.

The Relevance of Origin

For coloured gemstones, this is a point to be considered, with the top emeralds mined in Colombia, the finest rubies coming from Burma, and for sapphires Kashmir. However, it is important to remember that attractive gemstones do come from many different localities, and it is all about the beauty of the colour and the budget available.

The Best Care for Coloured Stones

One golden rule is to never carry gemstones in a pouch, as if stored with other stones, a diamond will scratch another diamond, and any stone softer than it. Sapphires will scratch everything that is softer than them, and so on, down the scale.

By Eliza Scarborough



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