Topaz is a silicate mineral that comes in a variety of colors, with the most common being yellow. However, it can also be found in shades of blue, pink, green, and even colorless. The color of topaz is influenced by factors such as impurities and the presence of radiation. Blue topaz, for example, is often treated to enhance its color. In addition to its beauty, topaz is the birthstone for the month of November and is associated with the zodiac sign of Sagittarius. It is valued in jewelry for its hardness and brilliance, making it a popular choice for rings, necklaces, and earrings.