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- ...
Niobium is a light weight heat resistant metal. The hardest material known is still Diamond (Mohs Hardness 10) Tungsten Carbide is one of the hardest and most durable metal alloys, Mohs 9 There are forms of Carbon Steel that do very well for strength and hardness.