Nobel Knight

I woke up to find these pictures on my computer. My son had sent them, he has remote access to my computer and can suprise me with such things. This clay creation was made by a guy that he works with at CompUSA. I guess it's made out of a soft clay that can't be fired and doesn't dry up to quickly. I don't model so I know little about clay. Anyone know of a way to harden or preserve this type of clay? Would this artwork sell?