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#An ancient term for ironstone, North Staffordshire, U.K.
#A large crystalline mass of limestone containing coral in position of growth, surrounded by shale and impure bedded limestone. See also: [[caballa ball]]
#A nodule or large rounded lump of rock in a stratified unit; specif. an ironstone nodule in a coal measure. Syn: [[ball]]

Source: Dictionary of Mining, Mineral, and Related Terms