A lot of the material dates from the early middle ages, like the 11th century, and it seems that there weren't such strong ideas about what Mary should look like, so there was quite a lot of variation......
see?
All of these are the classic Madonna with Jesus on her knee.
This one below is my favourite I think....
I think these ladies are lovely and I adore the variation of expression and beauty. They are not all teh same classic Madonna face and expression that became codified later, and they are charming. When we get later into the Renaissance, things got a little creepy.....check these two out....These are statues to saints who hold, embedded in their chests, parts of their now dead bodies....
I am, however, somewhat suspicious, as one has a skull and no jaw, and the other a jaw and no skull....and those teeth!!!
Creepy.