Boron is a brown powder or hard silvery chunks in its allotropes, the pure form of its atoms. It is very hard; just below diamond, 9.5 on the Mohs scale.
Boron's various compounds are very hard; one example is boron carbide, B^4C. It is over 9 on the Mohs scale. It is used in various applications, such as bulletproof armoring and abrasive, which is used to remove the top layer from any hard object to clean it, like sandpaper.
The atomic number is 5 and the mass is 10.81 amu