Boron is a Block P, Group 13, Period 2 element. The electronic configuration is [He] 2s² 2p¹. In its elementa form boron's CAS number is 7440-42-8. The boron atom has a radius of 79.5.pm and it's Van der Waals radius is 200.pm. Boron has an energy band gap of 1.50 to 1.56 eV, which is higher than that of either silicon or germanium. Optical characteristics include transmitting portions of the infrared. Boron is a poor conductor of electricity at room temperature but a good conductor at high temperature. Amorphous boron is used in pyrotechnic flares to provide a distinctive green color, and in rockets as an igniter Boric acid is also an important boron compound with major markets in textile products. Boron compounds are also extensively used in the manufacture of borosilicate glasses. The isotope Boron-10 is used as a control for nuclear reactors, as a shield for nuclear radiation, and in instruments used for detecting neutrons. Boron nitride has remarkable properties and can be used to make a material as hard as diamond. The nitride also behaves like an electrical insulator but conducts heat like a metal. Boron also has lubricating properties similar to graphite. Boron was first discovered by Sir Humphry Davy and J.L Gay-Lussac in 1808.