C: The Uncooperative Mineral
A type of mineral that's always causing trouble. Like, have you ever tried to clean coal from a rug? Forget about it. It's like trying to scrub off a bad habit.
Etymology: Coal-ictionary sources indicate that coal was first discovered in 1800 BCE by a caveman with a bad habit of getting dirty.
Example sentence: "I'm so sick of cleaning up after this coal dust explosion in the break room."
See Also: Coal-ictionary Definition 2, The Unreliable Source