Dealer Offering Item for Sale: New Directions - Gems
In antiquity all yellow and brown gemstones, even green ones were called "Topaz". The name most probably derived from a the 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 is a silicate mineral of aluminium and fluorine with the chemical formula Al2SiO4(F, OH)2. Topaz crystallizes in the orthorhombic system
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.
While blue topaz does exist in nature the vast majority of the popular Blue Topaz sold around the world has been 'treated' in one way or another. To get the classic Swiss Blue or London Blue, the untreated usually colorless gemstone is first exposed to radiation and then heated. The valuable Imperial Topaz is not usually treated although some stones with a pink shade can be heated to enhance the vividness of the pink. Some Topaz gemstones such as Mystic or Azotic are enhanced with a thin coating to give rainbow color effects. The NRC requires all irradiated gemstones to be stored in a secure facility after treatment. While in storage, the gemstones must be monitored until their residual radiation declines to a level that they are safe for use in jewelry. This procedure assures the safety of blue topaz treated within the United States.
The largest Topaz producer is Brazil. Other sources are in Pakistan, Afghanistan, India, China, Burma (Myanmar), Sri Lanka, Japan, Russia, Ukraine, Australia, Madagascar, Namibia, Nigeria, Zimbabwe, Mexico, and the U.S. (California, Utah, and New Hampshire).
