In the Hindu religious tradition, the tulsi, or holy basil, plant serves both as an important symbol and also as a popular medicinal remedy.
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 nitridâ¦e at 18% stronger then diamonds they are both extreamly rare natural minerals sources http://www.newscientist.com/article/dn16610-diamond-no-longer-natures- ...
About 94% of the six million known compounds contain carbon, far more than any other element. Carbon, in the form of diamond, is the hardest natural material on Earth. Carbon is found in a wide variety of rocks, such as chalk and limestone.