When buying rubies, ruby jewelry or any type of gemstones or gemstone jewelry it is important to know of a gemstone's possible treatments, synthetics and imitations. Ruby and sapphire are commonly heat treated to improve their color. Heat treating ruby and sapphire is so common that most people have never seen a ruby or sapphire that has not been heat treated. Heat treating rubies can make rubies have a more vibrant and valuable red color, remove some brown coloring from certain rubies and even improve the clarity of some rubies. Synthetic rubies are rubies that have been grown in a lab as opposed to growing in nature. Synthetic rubies have the same chemical composition and physical properties as a natural ruby and can’t be identified as synthetic with the naked eye. There are several methods used to grow synthetic rubies. Some methods produce rubies in a matter of hours that are normally easy for a gemologist to separate from natural ruby. Other methods can take several months to produce synthetic rubies and can be much more difficult to separate from natural ruby. Often it requires a well trained eye to separate flux grown synthetic ruby from natural ruby. When you buy ruby any treatments or synthetics must be disclosed by the seller.