Every Topaz represents different planets and signs depending on its color. Therefore, the fingers to wear the ring on depends on the type of Topaz as well as the suitability of the wearer. A Yellow Topaz should be worn on the index finger of the working hand while a Blue Topaz should be worn on the middle finger of the working hand. Similarly, a White Topaz should be worn on the ring finger of the working hand, but this is suggested only for males.
It is advised to consult an experienced Astrologer before buying gemstones as they can guide you better on which gemstone suits you, based on your birth-chart and sun-sign.
GemPundit offers free Gem consultation to help you find out the gem that suits you!