Fluorine
Fluorine is a highly reactive and dangerous element. It is encountered in nature in a stable version called fluoride, and it is in this form that is added to everyday goods such as toothpaste. It is essential to humans, but only in very small amounts, as it doesn’t take much before it becomes toxic to us.
Indium
Indium was used to solve two main problems that stood in the way of lcd screens.
One of indium’s oxides enables conductivity and circuits without the use of wire. Doped with tin to form Tin Oxide (ITO), this ITO has 2 essential properties and is the ONLY material which, in the form of thin films (typically one hundreth of a micron thick) has a v.high electrical conductivity and is nearly completely transparent over the whole visible spectrum making it neutral in colour.