The topaz is one of the most famous and coveted gemstones, and has been for many hundreds of years. Topaz comes in a variety of colours, with yellowish tones appearing most frequently, but also red, violet, blue and colourless variations. A topaz usually has a vitreous luster and is transparent or translucent. The purer a topaz is in its composition, the more colourless and transparent it is. The origin of the name cannot be clarified unambiguously, but a relationship to the word tapas from Sanskrit, which means fire and glow, is possible. This mineral is often also known under other names such as Finders Diamond, Killiecrankie Diamond, Mogok Diamond or Saxon Diamond. As this name indicates, the topaz is similar to the diamond, but it is an island silicate and not a carbon modification. A prominent example for the confusion of a topaz with a diamond is the Braganza diamond. Thought to be a diamond, in 1740 a topaz was placed in the crown of Portugal. If topaz is used as a gemstone today, it is of high quality but relatively cheap due to its frequent occurrence.