I was taken from a mine and placed in a wooden box, never to be opened again, yet I am used by almost everyone.
What am I?

I was taken from a mine and placed in a wooden box, never to be opened again, yet i am used by almost everyone.
What am i?

I'm thinking the answer may be salt. Salt comes from a salt mine, is placed into a salt shaker (which may be a form of a wooden box), and the salt shaker is not opened again.

Pencil lead

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