How should you assess a blue topaz’s quality and value?

As there’s no established grading method for coloured gemstones, our gemmologist recommends evaluating each blue topaz individually.

He does this in the same way as with diamonds – by clarity, colour, cut and carat weight.

With blue topaz, clarity is the foremost consideration, followed by vibrancy of colour and a skillful cut.

COLOUR

Blue topaz can range from a very light blue to a deeper blue colour. It can also have a slightly turquoise hue, reminiscent of aquamarine. Consumers should be aware that naturally occurring blue topaz is extremely rare. Therefore the blue variety used in jewellery is almost always obtained by heat treating or irradiation of colourless topaz. This is not considered to alter the gem’s durability.

CARAT

Natural topaz is found as crystals that are considerably larger than those of many other precious stones. Consequently, its per-carat price does not rise much as the size of the gem increases. It is therefore an affordable precious, blue stone that adapts well to larger jewellery.

CLARITY

When buying topaz jewellery, always look for a gem with excellent clarity. A topaz that is as pure as possible – with no imperfections that are noticeable to the naked eye – will always have the best sparkle. Brazilian topaz is known for its large, clear crystals. It is a good gemstone to buy if you’re looking for a big and dazzling precious stone at very affordable value.

CUT

Topaz is a very versatile gem when it comes to shape. Because it is often found as large crystals, topaz cutters are not too restricted by price and can therefore afford to lose some of the gem. Emerald and cushion cuts are popular, but you’ll also find topaz in round, pear, oval and marquise cuts – as well as triangles or fantasy designer shapes.

Naturally occurring blue topaz is extremely rare. That’s why virtually all blue topaz used in jewellery is heat or irradiation treated. Reputable jewellery retailers will always declare this on their products.

Unlike sapphires and rubies where heating is not recommended, treated blue topaz is perfectly accepted by gem experts and consumers. A professional treatment won’t weaken the gem’s crystal structure.

Topaz is a natural crystal. Due to the particular way in which it is structured, it can be brittle if knocked or exposed to sudden changes of temperature.

That’s why our gemmologist would advise you to avoid ultrasonic or steam cleaning. Instead, use hand-warm water and a bit of soap, and wash your topaz very gently with a cloth or a soft toothbrush, patting it dry afterwards.

During the 18th century gold rush, Brazilian topaz became extremely popular amongst European aristocracy. The enormous Braganza topaz was set in the Portuguese Royal crown, and the Parure necklace of Maria Pavlovna, belonging to the Swedish royal family, is made with Brazilian topaz.

Catherine Middleton has been known to wear a pair of blue topaz and diamond drop earrings on social occasions. Hollywood is also very fond of the blue gem, famously worn at award ceremonies by Cate Blanchett, Katy Perry, Taylor Swift and Jennifer Lopez.

The Programa Royal Collection is a natural heritage gem collection based in Madrid, Spain. One of its most famous gemstones is the Marbella Topaz, the world’s biggest blue topaz.

At 8,225 carats and expertly cut into an oval shape, it is breathtakingly pure and transparent. The Marbella Topaz can be admired at the Programa Royal’s Art Natura complex in Madrid.

In mythology, topaz is portrayed as a gem of peace and healing. It was first found by the Romans over two millennia ago on the Island of Topazios in the Red Sea. They believed it could protect its wearer from enemies and bring reconciliation.

The gem was also worshipped in old Egypt, where it was said to hold mystical powers given by the sun god Ra. In South America, many tribes believed topaz could dispel sickness when the moon was full.