Diamonds are the hardest known substance
Diamond. a very hard material that is the hardest substance ever, or at least discover to be the hardest substance on EARTH THAT IS
The hardest naturally occurring substance is called diamond. It is a form of carbon.
Diamond use to be the hardest known natural substance now it is the mineral lonsdaleite at 58% stronger then diamond is the first the second hardest is wurtzite boron nitride at 18% stronger then diamonds they are both extreamly rare natural minerals sources http://www.newscientist.com/article/dn16610-diamond-no-longer-natures-hardest-material.html
diamond is the hardest and graphite is the softest
the hardest element is osmium, number 76 on the periodic table.
A diamond
Enamal is tha hardest part of human body..
Enamel is the hardest substance in the human body.
Diamond is the hardest known substance.
clay,wood,plastic,iron
Enamel which is the coating on your teeth
Diamond 10