Aquamarine vs Blue Topaz: What is the Difference?

Several Blue Topaz Gems

Aquamarines are incredibly similar to Blue Topaz, so why is there a massive difference in price?

What does a Blue Topaz look like?

A Blue Topaz Ring

In its pure form, Topaz is white but impurities make it change colour. The colour of a topaz is determined by the levels of iron and chromium that are in the stone. However, a blue topaz can be found naturally but it is incredibly rare and the colour tends to be very light.

Blue Topaz meaning

Dating back thousands of years its name derives from the word Topazos, which is an ancient island in the Red Sea. It is thought to heal both physical and mental illnesses as well as prevent death.

A topaz rates 8 on the Mohs scale meaning that it is a lot harder than other gemstones and slightly harder than an aquamarine which rates 7.5 to 8 on the Mohs scale.

A topaz has a perfect cleavage which means that it is more susceptible to scratches or fractures. You can clean a blue topaz gemstone by soaking it in a bowl of soapy warm water for 20-30 minutes then gently rubbing a soft bristled toothbrush over it.

What does an Aquamarine look like?

An Aquamarine Gem Ring

The colour of an aquamarine tends to vary along the blue-green colour spectrum. The majority of aquamarines are of light blue colour, but the most expensive and coveted aquamarines are dark blue.

Aquamarine meaning

The name aquamarine derives from the Latin words, aqua- meaning ‘water’ and marina- meaning ‘of the sea’.  Aquamarines have been linked to the Romans and Greeks, and the gemstone was considered to be sacred by Neptune, Roman God of the Sea.

Aquamarine is 7.5-8 on the Mohs scale, which means that it has a high level of toughness, and this generally protects it from scratches. To clean an aquamarine gemstone you should use warm soapy water. It can also be cleaned using ultrasonic and steam cleaners unless the stone has liquid inclusions or fractures.

How to tell the difference between blue topaz and aquamarine

When buying an aquamarine gemstone you should be careful. A light blue topaz is a lot cheaper than an aquamarine, and it is very hard to differentiate between the two. The two are so similar that fraudulent jewellers sometimes advertise and sell a topaz as an aquamarine instead.


By using a jewellers loupe you can tell the two gemstones apart. If you see two refraction lines when looking through a jewellers loupe at a gemstone you will know that it is, in fact, a blue topaz and not an aquamarine.

So why is an aquamarine more expensive than a blue topaz?

Simply because a blue topaz is more accessible than an aquamarine. This is due to the fact that a blue topaz is usually produced by colouring a white topaz through irradiation and intense heat. Aquamarines on the other hand are natural so are a lot rarer and more desirable as a result.

If you are looking for a beautiful aquamarine ring visit our stunning gemstone collection here.

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