The jewellery industry recognizes the highest quality gemstones by purity of their hue, the depth of tone,
and the colour saturation. The best value is in colours that include "slight" traces of other
colours, are not too light or dark, and have a lot of saturated colour. Blue Nile offers some of the
highest-quality coloured gemstones available. Nearly all gemstones today, including Blue Nile stones, have been treated to enhance
their colour. The most common methods of treatment are heating, nearly always seen with aquamarine, citrine, amethyst, sapphire, ruby
and tanzanite, bleaching commonly seen with pearls, and irradiation performed on nearly all blue topaz.
Almost all gemstones contain inclusions. Even those most highly prized have at least some inclusions. Flawless gemstones are very rare and very expensive. The best value is found in gems that are lightly to moderately included, like those in Blue Nile gemstone jewellery. Emeralds are typically treated with colourless oil, wax or resin to minimise surface-reaching inclusions.
Unlike diamonds, with gemstones there isn't an "ideal" cut geometrically configured for maximum brilliance. But a high-quality gemstone cut is one that presents the most even colour, exposes the fewest inclusions, and displays the majority of the gemstone weight when set in jewellery.
The carat weight of a gemstone is not necessarily an accurate gauge for gemstone size. To help you judge
the size of a gemstone, Blue Nile lists the diameter of the gemstone when viewed from above - since if
the gemstone is set in jewellery; this is the only part of the gemstone that is visible.
Nearly all gemstones on the market, including gemstones offered by Blue Nile, have been treated to enhance their appearance. Gemstones
that have not been treated but exhibit desirable colour and clarity command extravagant prices. Some enhancement treatments are almost
universal, are permanent, and require no special care of the gemstone, such as heat treatment to enhance colour. Other treatments are
common, and may require more or less special care to avoid damage, such as infusion of colourless oil, wax or resin to improve clarity.
Every gemstone has unique characteristics. Considerations in every day care, how and when you wear your fine jewellery, will dictate longevity. View our
wear, care, and sizing page to learn more.