Don, Suzanne told me when she read this thread that Bartoli and Horne are NEVER contraltos, even though they may be given parts labeled contralto, because their voices are definitely mezzo soprano voices. They don't have the contralto sound to their voices, even though they may be given that role. Regarding this, the worst she said she has heard was when Charlotte Church, who has a light voice, was given the Habanera from Carmen to sing. Suzanne's further comments

"...For instance, a heavy quality
voice (be it mezzo or soprano sings the role of Carmen) - traditionally and because of the other voices and
orchestration of the composer.   The MOST ridiculous thing I ever heard was Charlotte Church singing the
Habanera from Carmen on TV. Her timbre is the lightest of soprano voices - and she has a real purity to the
tone - gorgeous in music for that kind of voice. And most ill advised attempting Carmen.   Neither Cecelia
Bartoli nor Marilyn Horn are true contralto voices, they are mezzo sopranos - not because of their range
but because of their timbre (and parentheically each started out as a soprano and as the voice matured, it
found its true range and type)." end quote

So, a mezzo is a mezzo, like Bartoli and Horne... a contralto naturally has even a weightier voice than a mezzo (not necessarily LOWER, just heavier timbre).

If you do a google search on Schumann-Heink or Schuman-Heink you'll find some interesting stuff (I keep finding different spellings of her name).

Maybe we are getting down to why true contraltos are rare today.

Alice