Boron!

Boron is a chemical element with symbol B and atomic number 5. It is a low-abundance element in both the Solar system and the Earth's crust and is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest proven boron deposits are in Turkey, which is also the largest producer of boron minerals.

This rare element is a metalloid; which means that it can can act both as an acid and a base, and it also behaves as a semiconductor.  Boron never occurs in a pure state in the wild, and can only be purified with difficulty by chemists. Boron is a poor conductor of electricity, and is fairly non-reactive, although it is water soluble. The most common uses for boron-containing compounds includes a bleach for clothing, a swimming pool disinfectant and to produce green flames.

About half of global consumption of boron compounds is as additives for glass fibres in boron-containing fibreglass used for insulation or as structural materials. The next leading use is to make boron polymers and ceramics, that play specialised roles as high-strength lightweight structural and refractory materials. Borosilicate glass glassware is used for its greater strength and breakage resistance (thermal shock resistance) than ordinary soda lime glass.

For more information visit:-
http://en.wikipedia.org/wiki/Boron
http://www.theguardian.com/science/punctuated-equilibrium/2011/mar/11/1