Gemstone Facts: In antiquity all yellow and broen gemstones, even green ones were called "Topaz". The name most probably derived fromathe name of an island in Red Sea, now Zebirget, formerly Topazos. The most Valuable is pink and blue. Topaz color usually is often enhanced by the process of heating or radiation to obtain a desired color.The dark blue topaz stones that have been processed through a treatment called “London blue topaz” whereas blue was called “Swiss blue topaz” and light blue are called “Sky blue topaz”. Topaz stone became one of the excellent precious stone that targeted by collectors. It can be seen from the growing popularity and the increasing of sales charts around the world.