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Typically red in color, rubies are one of the most popular gemstones.The popularity of natural rubies led scientists to create synthetic rubies in laboratories. Although synthetic stones appear nearly identical to natural rubies, they are not considered the same. When synthetic rubies are sold, they are identified by the words synthetic, created or cultured.

Natural Rubies

Often valued at a higher price than diamonds, natural rubies continue to be highly sought after. Rubies rank a nine on Mohs scale of hardness, making them a very durable gemstone. Ruby mining takes place in several countries, including Afghanistan, Kenya, Madagascar, Sri Lanka, Tanzania, Thailand and Vietnam. Rubies often undergo heat treatment to improve their color and clarity. Oil or resin fills fractures to improve their appearance.

Synthetic Rubies

The popularity of rubies led scientists to create synthetic rubies in laboratories. Synthetic rubies contain almost the exact same chemical composition and physical properties as natural rubies, but are sold around the world for a fraction of the price of natural rubies. Synthetic rubies often appear brighter and more vivid than natural rubies.

Process to Create Synthetic Rubies

Scientists began creating synthetic rubies in 1902. Two of the most common methods of creating synthetic rubies include flame fusion and flux fusion. The flame fusion process produces rubies within a few hours. Raw gem material is melted and then cooled, causing it to recrystallize. The flux fusion method is similar to the flame fusion process, but it takes months for the material to recrystallize and form synthetic rubies.

Differences in Appearance

Traditional methods of gemstone testing are not always able to identify synthetic rubies. Determining if a ruby is natural or synthetic typically requires the expertise of a gemologist and a high powered microscope. Natural rubies often include inclusions or bubbles. The inclusions in synthetic rubies appear slightly different under a high powered microscope. High powered microscopes can also detect tiny gas bubbles or curved striae in synthetic rubies. Rubies created with the flame fusion technique also reflect light differently than natural rubies.