Genuine Blue Topaz Oval-Cut Stud Earrings .925 Sterling Silver Dainty & feminine Stone Length (up and down): Approx. 6mm Stone Width (side to side): Approx. 4mm New without tags. About Topaz: Topaz is a durable, silicate mineral. A precious stone, it is allochromatic, which means that its color is caused by defects in its crystal structure rather than by an element of its basic chemical composition. Most commonly found in a white or transparent shade, it is often treated to produce vivid blue, pink, or red colors. Blue Topaz is known to provide mental clarity and calmness.