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1 " All the elements other than hydrogen and helium make up just 0.04 percent of the universe. Seen from this perspective, the periodic system appears to be rather insignificant. But the fact remains that we live on the earth… where the relative abundance of elements is quite different. "
― Sam Kean , The Disappearing Spoon: And Other True Tales of Madness, Love, and the History of the World from the Periodic Table of the Elements
