i was thinking about trying this. i dont know how safe it is. i would be concerned about how clean it is or the place where it came from , i guess it is full of dust. i would want to know where it was mined and something about the company.
only problem i was reading others post about this . this makes since: if it gets wet it turns into clay , well then it wont work and you got a belly full of clay. so that kinda scared me away from it.