Topaz can be found in a variety of colours: green, yellow, red, pink, gold... and also in blue, which is undoubtedly the most popular for this gemstone. This colour is difficult to find, however, and some of the most important deposits are located in England (Cornwall), Scotland and Northern Ireland. The deep tones of blue topaz add depth to any piece of jewellery; perhaps that's why it's one of the most popular gemstones.
Color: Colorless, yellow, orange, blue, pink, violet, light green
Moh's hardness: 8
Chemical composition: Al2 [(F,OH)2[SiO4] Fluor containing Aluminium silicate