Ruby is an extremely strong stone. It ranks 9.0 on the Mohs scale of mineral hardness, placing it directly under the diamond and moissanite (a diamond ranks 10.0 on the scale and moissanite falls in between diamonds and rubies). Natural rubies contain imperfections, including color impurities. Additional imperfections are inclusions of rutile needles referred to as “silk.” These imperfections play an important role in detecting artificial rubies. Heat treatments are very common among most rubies today. Almost every ruby undergoes some sort of treatment, heat treatment being the most common. It is conducted prior to the cutting of the stone. That being said, there are a few high-quality rubies that have not been treated, which of course demand very high prices.

Ruby Sample