An Intro to Gemstone Treatments and Enhancements
What are Enhancements?
An Intro to Gemstone Treatments and Enhancements
Heat Treatment
Heat treatment is a method used to permanently enhance the colour and/or clarity of a gemstone by applying heat. The temperature and time required to alter gemstone colour depends on the stone. For example, rubies and sapphires require more heat than other gemstones. While some stones become more colour-saturated after a heat treatment, stones like amethyst will lighten under high temperatures.
Some may worry that high heat will damage the gemstones, but most gems are formed under high temperatures, and heat will not have a negative effect on the stone. Heat treatment is one of the most common practices in gemstone enhancement, and without it, the availability of fine gemstones would be significantly reduced. For this reason, heat treatment is an accepted practice by the jewellery industry and the American Gem Trade Association.
Infusion
Infusion is the practice of filling a gemstone with a material like oil, wax, glass or resin in order to improve gemstone clarity. Like most gemstone enhancement procedures, this is a method that began centuries ago with the purpose of enhancing a gemstone’s overall appearance to the naked eye.Coating
Coating adds additional protective layers to gemstones, varying in form and function. One of the most common materials used for coating gemstones is wax, which can improve the stone’s lustre and protect gems from external oils and other damage. In other cases, artificial polymer, resin and oils are used to coat the gem and improve sturdiness and appearance. Coating is often used on gemstones cut into the shape of a cabochon gem, like turquoise and jade, and is also very commonly used on pearls.Bleaching
Bleaching is commonly used to lighten the appearance of a gemstone. Chemicals like bleach and hydrogen peroxide are the most common lightening agents for gemstones. Bleaching also removes unwanted colour in order to even out the appearance of the stone.
This is a relatively stable enhancement method for gems that won’t be re-cut or polished following the treatment, but bleaching may have a negative impact on the gem’s durability. For this reason, the bleaching method is often combined with an impregnation treatment to improve strength and durability.
Dyeing
Dyeing involves adding a coloring agent into a gemstone to give it a new colour, intensify its existing colour or to improve the overall colour uniformity. Since colour is the most important attribute of a gemstone, dyeing is one of the oldest enhancement methods in the industry.
Some believe that dyeing a gemstone decreases its value and renders it artificial, but this treatment only enhances its natural pigmentation—a dyed stone looks nearly identical to an undyed, much more expensive jewel.
Irradiation
Similar to heat treatment, irradiation is an enhancement method that uses radiation to alter and improve the colour of a gemstone. Irradiation involves levels of ionizing radiation, which changes the atomic properties of the gemstone and results in a visible improvement in the gemstone's appearance.
The most common concern about irradiation is whether the radioactivity is safe for the wearer, and the answer is yes! There is no evidence of any harm from wearing an irradiated gemstone.
New and Future Enhancement Technologies
Gemstone enhancement techniques have been around for centuries and continue to be developed every year in order to provide consumers with the most beautiful gemstone jewellery available at an affordable price.
We are committed to working with the best industry professionals and gemmologists to maintain our high-quality standards when it comes to gemstone enhancement.
What to Look For When Buying an Enhanced Gemstone
Vivid Colour
The gemstone may have been treated with heat or irradiation.Even Colour
The gemstone may have undergone dying or bleaching.Eye-clean Appearance
If the gemstone appears perfectly clear, it may have undergone an infusion.
Our Coloured Gemstone Enhancement Approach
Common Enhancements by Gemstone
- Gemstone
- Enhancement method
- Agate
- Heated or dyed to improve colour.
- Amber
- Heated to improve colour and clarity.
- Amethyst
- Heated to improve colour.
- Apatite
- Heat
- Aquamarine
- Heated to improve colour and clarity.
- Black Diamond
- Heated or irradiated to alter colour.
- Black Onyx
- Dyed.
- Black Spinel
- None.
- Blue Topaz
- Heated and/or irradiated to alter colour. Thermal coated to alter colour.
- Carnelian
- Heated to improve colour.
- Chalcedony
- Dyed.
- Chrome Diopside
- None
- Citrine
- Heated to improve colour.
- Coral
- Coated or impregnated with colour less substances to improve surface uniformity or durability. Bleached or dyed to enhance colour.
- Diamond
- None.
- Emerald
- Infused to improve clarity and/or colour.
- Fire Opal
- None.
- Garnet
- None.
- Iolite
- None.
- Kunzite
- Heated or irradiated to improve colour
- Labradorite
- None.
- Lapis
- Dyed.
- Moonstone
- None.
- Morganite
- Heated to improve colour and clarity.
- Opal
- Coated to alter surface consistency and durability.
- Pearl (natural and cultured)
- Bleached, dyed, polished and coated.
- Peridot
- None.
- Prehnite
- None
- Quartz
- Green/Lemon: Irradiated to improve colour.
- Smokey: Heated to improve colour.
- Blue: Dyed.
- Rutilated/Rose/white: None.
- Ruby
- Heated and/or infused to improve colour and clarity.
- Sapphire
- Heated and/or infused to improve colour and clarity.
- Spinel
- None
- Tanzanite
- Heated to alter colour and clarity. Infused to alter colour and clarity.
- Tourmaline
- Irradiated to improve colour.
- Turquoise
- Coated or impregnated with colour less substances to improve surface uniformity or durability.
- White Agate
- None.
- White Topaz
- None.
- Multi Gemstone Tennis Bracelet
- 3-Stone Elongated Cushion Cut Garnet and Purple Rhodolite Ring
- Aquamarine Rope Stud Earrings
- Oval Ruby and Diamond Sunburst Halo Ring
- Petite Oval Amethyst Bracelet
- London Blue Topaz Cushion Earrings
- Bezel-Set Pear-Shaped Ruby and Diamond Stacking Ring
- Petite Oval Multicolor Gemstone Bracelet
Learn More About Gemstone Characteristics
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