Here a photos,published by an italian magazine,"Panorama".

http://www.imagebam.com/image/3045c2120521834

This photos (and others) are made in a actual Indian coal mine,in Bokapahari region.
Many miners are woman (in extreme poverty condition),and as visible,they carry the coal load
over the head,walking barefeet on the mine surface !

Basically, what in Italian mines happened 70 years ago, it still happens now in India

Here are some other photos and the article about (is in italian) :

http://blog.panorama.it/foto/2011/02/14/vi...to?refresh_cens

Could you imagine how tough their feet would have to be. they probably did this all day long.

The peasant girls...poor village girls and women of India...even more than the Bollywood actresses...are what I consider sexy. They live barefoot..are always naturally and casually barefoot....and these that worked in the coal mines...what dirty, black, sexy feet they have.

Of sure they did this work all day long everyday,and probably for all the life

I wonder if there's much mud they walk in!
On a serious note, lack of shoes is considered a sign of poverty, sadly.