Most blue topazes come out of the earth colorless or pale blue. A two-step heat and radiation laboratory treatment is then used to turn these stones vivid greenish blue. Blue topazes are not only beautiful but inexpensive.
Through the ages, topaz has been popularly associated with wealth. This is likely due to its more common yellow color, which led some to believe that topaz had the mystical ability to attract gold.
Blue topaz are refered to by trade names such as "London Blue," "Swiss Blue," and "Sky Blue." London Blues have a dark steel blue or grayish blue color. Swiss Blues show a highly saturated greenish blue. Sky Blues show pale blue colors and may somewhat resemble aquamarines in hue and tone.