As a kid I remember my late mum using a porous type, black bubbly stone like a rasp in a way, to rub off the dead rough skin on the heels of her feet, it was called I think a pommous stone (sp) or something like that?

Anyway as is usually the case, im now my mums age and getting the same rough heels, if I pick the skin it ends up sore and bleeding, do they still make these black stones?