Silicon

Silicon is a gray, shiny metalloid and, after oxygen, the most common element in Earth's crust. It is never found pure; it is bound to oxygen as silicon dioxide in sand, quartz and most rocks. Heating quartz with carbon in an electric furnace frees it as metallurgical-grade silicon, which can then be purified into polysilicon for chips and solar cells.

Silicon is a semiconductor: it conducts electricity only under the right conditions, which is what makes transistors possible. In the television it also strengthens the aluminum alloy and helps it flow when cast, and forms the glassy framework of the low-k dielectric that insulates the wiring inside chips.