A contralto is a type of classical female singing voice whose vocal range is the lowest female voice type. The contralto's vocal range is fairly rare; similar to, but different from the alto, and almost identical to that of a countertenor. The contralto voice type is generally divided into the coloratura, lyric, and dramatic contralto.
Coloratura—The coloratura contralto has a light, agile voice ranging very high for the classification and atypically maintains extensive coloratura and high sustaining notes, specializing in florid passages and leaps. Given its deviations from the classification's norms, this voice type is quite rare.
Lyric—The lyric contralto voice is lighter than a dramatic contralto but not capable of the ornamentation and leaps of a coloratura contralto. This class of contralto, lighter in timbre than the others, is the most common today.
Dramatic—The dramatic contralto is the deepest, darkest, and heaviest contralto voice, usually having a heavier tone and more power than the others. Singers in this class are rare.
The following video shows contralto Nathalie Stutzmann singing "Orfeo 55" by Handel.