Borax is also used mixed with water as a flux when soldering jewelry metals such as gold or silver.
Borax is used as a food additive in some countries with the E number E285, but is banned in the United States.
Borax occurs naturally in evaporite deposits produced by the repeated evaporation of seasonal lakes.
Borax is also a good flux for 'pre-tinning' tungsten with zinc, making the tungsten soft-solderable.
Borax is also easily converted to boric acid and other borates, which have many applications.
A mixture of borax and ammonium chloride is used as a flux when welding iron and steel.
The origin of the name is traceable to the Medieval Latin borax, which comes from the Arabic buraq, which comes from either the Persian burah or the Middle Persian burak.
The term borax is used for a number of closely related minerals or chemical compounds that differ in their crystal water content, but usually refers to the decahydrate.
Borax, also called sodium borate, sodium tetraborate, or disodium tetraborate, is an important boron compound, a mineral, and a salt of boric acid.