Common ruby treatments & enhancements

Rubies often have fractures and inclusions that can affect their appearance and value. Oiling, resin filling and fracture filling are used to improve the appearance of rubies by filling these fractures and inclusions and making the ruby appear more transparent. Clarity enhancement is also used to improve the clarity of rubies, by drilling a small hole in the ruby and inserting a substance that hardens and improves the clarity of the ruby. Dyeing is also used to improve the color of rubies, by dyeing the ruby to make it appear more red.

As you might have realised many of the treatments that are used for emeralds are also used for rubies, such as oiling, resin filling, clarity enhancement and dyeing. Please read our article on emerald treatments and enhancements for more information.

However, there are some treatments that are specific for rubies and not for emeralds. One of them is heat treatment, which is a common treatment for rubies. The process involves heating the ruby to high temperatures, typically between 800 and 1800 degrees Celsius, in a controlled environment. The heat causes changes in the crystal structure of the ruby. Heat treatment can improve the color of rubies by removing impurities, such as iron and titanium, that can cause a yellow or brown tint in the ruby. The heat causes these impurities to evaporate and the ruby becomes a more vibrant red color. Heat treatment can also improve the clarity of rubies by removing inclusions, such as rutile needles and liquid inclusions, that can make the ruby appear cloudy or hazy. The heat causes these inclusions to vaporize and the ruby becomes more transparent.

It's important to understand that heat treatment does not affect the durability of the ruby, only improves the color and clarity, and it's considered an acceptable practice in the gemstone industry. However, some heat treatments may lead to thermal stress and fractures, so it's important to look for high-quality heat treatment from reputable sources.

Another thing to consider is that the heat treatment process may vary depending on the quality of the ruby, the desired result and the method used. It's possible that some rubies may be heat treated multiple times, or with different methods, to achieve the desired color and clarity.

You might be wondering why heat treatment is not a common treatment for emeralds. Unlike rubies and sapphires, emeralds are typically not heat treated because the process can cause significant damage to the stone. The high temperatures used in heat treatment can cause the water and other impurities in the emerald to evaporate, which can cause the stone to become brittle, crack or completely shatter.

It's also important to note that some rubies may be treated with other treatments in addition to heat treatment, such as dyeing or clarity enhancement. This can further affect the value and durability of the ruby and it's important to be aware of these additional treatments when buying a ruby.