Blue John may refer to:
- Derbyshire Blue John, a form of fluorite mined in Derbyshire, England
- Blue John Cavern, a cavern in Castleton, Derbyshire where fluorite is mined
- Blue John Canyon, a canyon in Utah, United States, site of the Aron Ralston accident
- Blue John (album), an album by organist John Patton
- Lance-Constable Bluejohn, a character in the Discworld series, a member of Ankh-Morpork City Watch
- Blue John Gap, a fictional location in Arthur Conan Doyle's short story "The Terror of Blue John Gap"
Famous quotes containing the word blue:
“There were ghosts that returned to earth to hear his phrases,
As he sat there reading, aloud, the great blue tabulae.
They were those from the wilderness of stars that had expected more.
There were those that returned to hear him read from the poem of life,
Of the pans above the stove, the pots on the table, the tulips among them.
They were those that would have wept to step barefoot into reality....”
—Wallace Stevens (1879–1955)