Referred to as the ultimate blue gemstone, sapphires are said to represent honesty, loyalty, purity and trust. Now used commonly in engagement rings, this belief has become a popular tradition.
Blue sapphires are certainly the most well-known colour variety of sapphires, however, sapphires are not only blue, in fact they come in almost every colour of the rainbow: pink, yellow, orange, peach, and violet colours to name a few. Corundum crystals in their purest form are transparent, it is the traces of natural chemical elements that alter their hue. For example, blue sapphires, in their most classic shade of royal blue, get their distinct colour from the traces of iron and titanium. Other coloured sapphires, for example green sapphires, also have hints of iron and titanium, as well as copper. The amounts of these chemical elements present in sapphires determine its colour, and even when adjusted ever so slightly can change drastically.
Some rare sapphires display the phenomenon called “colour change”, in the most usual occurrence these sapphires appear blue in natural or even fluorescent lighting and can change to purple under alternative lighting such as incandescent.
Sapphire is the birthstone for September and the gemstone which commemorates the 5th and 45th wedding anniversaries.
Sapphires are available in a wide range of colours, not only blue. The rarest coloured sapphire is a peachy, pale coral variety known as padparadscha.
As a member of the corundum mineral family, along with rubies, sapphires measure 9 on the Mohs scale of hardness. This is second only to diamond – the hardest natural material known to man. Sapphires have excellent hardness and durability and are a great choice for jewellery worn daily, therefore suitable for engagement rings.