Carbon is the chemical element with the symbol C and has an atomic number of 7 with an atomic weight of 12.0107.
Things you might not know about Carbon:
1. Elemental carbon can take the form of one of the hardest substances (diamond) or one of the softest (graphite).
2. Carbon is made in the interiors of stars, though it was not produced in the Big Bang.
3. Carbon is the fourth most abundant element in the universe after hydrogen, helium and oxygen, and is the second most abundant element in the human body.
4. Another allotrope of Carbon is Buckminsterfullerenes, which includes the Carbon Nanotube. Carbon nanotubes have a tested tensile strength 8 times greater than steel.
See GC2XAY2 - Hydrogen, for an explanation about this series of caches.