What chemical element is denoted by the symbol Si?

Silicon is represented by the symbol Si, whilst silver has been given the symbol Ag, from the Latin 'argentum'. Tin is also given a symbol, Sn, taken from its latin name 'stannum' and Zirconium has the symbol Zr.

Silicon is the 14th element in the Periodic Table and was first isolated in a pure form in 1823 by Jöns Jakob Berzelius. It is the second most common element in the Earth's crust after oxygen. Indeed, it has a great affinity for oxygen and is mostly found as silicon dioxide (silica) or as various silicate minerals.

Silicon is widely used in the construction industry where silicates form the basis for cement and concrete. Silica is also an essential component of soda-lime glass used for windows and glass bottles. A more recent use of highly purified silicon is in the semiconductors found in computers and mobile phones; giving rise to the nickname 'silicon valley' for the area of California where many high-tech firms are based.