Topaz is a clear, crystalline form of aluminium and fluorine silicate. It exists in a variety of colours including white, yellow, yellow-brown, orange, light red, light blue, light green and (rarely) violet.
Topaz is a symbol of love and affection and was believed to aid sweetness of disposition.
Many stones sold as topaz are in fact citrine, which is lighter than topaz. (True topaz is far more expensive than citrine.)
Yellow and blue topaz may fade after long exposure to light.