Blue Nile's Coloured Gemstone Enhancement Policy

Blue Nile offers consumers only the highest quality, authentic gemstones. Our coloured gemstones undergo rigorous internal inspections by our trained gemologists to ensure they meet our stringent quality standards.

Due to their rarity and unique visual properties, nearly all coloured gemstones sold at fine jewellers, including Blue Nile, are enhanced using various techniques. Many of these techniques have been used for centuries. Coloured gemstones that have not been enhanced are very rare and command extravagant prices.

Our diamonds are not enhanced in any way, other than normal cutting and polishing.

Coloured Gemstone Enhancement Processes

There are many methods of enhancing coloured gemstones. We describe the most common enhancements below. For more information on coloured gemstone enhancements, see the American Gem Trade Association's Gemstone Information Manual.

  • Heat Treatment

    The application of heat to enhance the colour and/or clarity of gemstones has been a common practice around the globe for centuries. It is part of the standard polishing and finishing process for many coloured gemstones. As such, it is accepted by the jewellery industry and the American Gem Trade Association. The enhanced colour and/or clarity of heat-treated gemstones is permanent.

  • Infusion

    The filling of a gem material with an oil, wax, glass, resin or other material, coloured or colourless, to improve appearance. This process began centuries ago by gemstone merchants who found that immersing emeralds in oil or waxes made them look clearer to the unaided eye. This practice continues today with many coloured gemstones.

  • Coating

    The use of wax, resin or oil applied to the exterior of a porous coloured gemstone to protect the natural substance, and to improve sturdiness and appearance.

  • Bleaching

    The application of chemicals or other elements to lighten or enhance colour consistency.

  • Dyeing

    The act of adding colouring agents so that they permeate a coloured gemstone to enhance or alter colour.

  • Irradiation

    The alteration of a gemstone's colour through the use of radiation. This is often followed by a heating process. The enhanced colour of irradiated gemstones is permanent.

  • New and Future Technologies

    Techniques for enhancing coloured gemstones, either detectable or otherwise, are continually being developed. These may be difficult, or in rare cases, impossible to detect, even for the most sophisticated laboratory. Blue Nile will continue to work with industry groups and gemological experts who are committed to the identification and disclosure of new and future techniques in order to maintain our stringent quality standards.


Basic Gemstone Care

While gemstones are durable, they require varying levels of care. For example, some gemstones are especially vulnerable to household chemicals and temperature changes. Cleaning gemstones presents special challenges. While many gemstones should be cared for by following our basic care guidelines below, please refer to our Gemstone and Pearl Care and Enhancement Overview to understand the care requirements for your specific stone. If you still have questions, please contact Blue Nile customer service.

  • Cleaning

    After removing your gemstone jewellery, clean it by following the directions on a non-abrasive jewellery cleaner. Make sure that the jewellery cleaner specifies that it is safe to use with your gemstone. Use a soft cloth to remove any remaining dirt or other residue.

  • Storing

    Store your gemstone jewellery in a lined case or a soft cloth, so the gems do not touch each other or parts of other jewellery. Gemstones are harder than gold, silver, or platinum and can scratch the surfaces of your other fine jewellery if they are not kept separate.

  • Wear

    While it's true that gemstones such as ruby and sapphire are second only to diamond on the hardness scale, it is not a measurement of their indestructibility. It means that these gemstones are able to resist scratching almost as well as a diamond. Abrasive surfaces, harsh chemicals, and sharp blows can damage even the hardest gem. Your gemstone jewellery should be the last thing you put on when getting dressed and the first thing you take off at the end of the night. Store your gemstones carefully and they will be enjoyed for generations.


Gemstone and Pearl Care and Enhancement Overview

Gemstone Accepted Enhancements Gemstone Care

Amethyst

Heated to alter colour.

Basic Gemstone Care.

Aquamarine

Heated to alter colour and clarity.

Basic Gemstone Care.

Black Onyx

Dyed.

Basic Gemstone Care.

Blue Topaz

Heated and/or irradiated to alter colour.

Basic Gemstone Care.

Citrine

Heated to alter colour.

Basic Gemstone Care.

Diamond

None.

Basic Gemstone Care.

Emerald

Infused to alter clarity and/or colour.

Do not use ultrasonic cleaning. Avoid sudden temperature changes, chemicals, perfume, cosmetics, and hairspray.

Garnet

None.

Avoid sudden temperature changes.

Opal

Coated to alter surface consistency and durability.

Do not use ultrasonic cleaning. Avoid sudden temperature changes, chemicals, perfume, cosmetics, and hairspray.

Pearl (natural and cultured)

Bleached, dyed, polished and coated.

Do not use ultrasonic cleaning. Avoid sudden temperature changes, chemicals, perfume, cosmetics, and hairspray. For more information, visit Pearl Education.

Peridot

None.

Basic Gemstone Care.

Pink Tourmaline

Irradiated to alter colour.

Do not use ultrasonic cleaning and sudden temperature changes.

Rose Quartz

None.

Do not use ultrasonic cleaning.

Ruby

Heated to alter colour and clarity. Infused to alter colour and clarity.

Avoid household chemicals and ultrasonic cleaning.

Sapphire

Heated to alter colour and clarity. Infused to alter colour and clarity.

Avoid household chemicals and ultrasonic cleaning.

Tanzanite

Heated to alter colour and clarity. Infused to alter colour and clarity.

Do not use ultrasonic cleaning and sudden temperature changes.

White Agate

Dyed.

Basic Gemstone Care.