Rubidium was discovered by Kirchhoff and Bunsen, in 1861, when they noticed the existence of new spectral lines in a lepidolite sample. Its name derives from the Latin rubidus (dark-red), due to the zone of its spectral lines. The preparation of the metal was tried by Bunsen, but he never got samples with more than 18% of rubidium. The separation of the metal was only accomplished by Hevesy, through the hydrolysis of melted rubidium hydroxide. Later, Hevesy also obtained rubidium through the reduction of that hydroxide sodium, potassium or hot aluminum.