What is put on glass to make it a mirror?

Actually as a matter of fact you put a special liquid which is a element on the glass. This special liquid is called Mercury. In addition, this liquid also found in thermometers. It a verrrrrrrrrrrrrrrrrrrrrrry bad. It can kill you instantly. one side of the glass is coated by metal the other side is reflecting surface so you can look at your self before you walkout in your makeup or dress