AD COELUM DOCTRINE
ad coelum doctrine.The common-law rule that a landowner holds everything above and
below the land, up to the sky and down to the earth’s core, including all minerals. • This rule
governs ownership of “hard” (immovable) minerals such as coal, but not “fugacious” (volatile)
minerals such as oil and gas. Cf. RULE OF CAPTURE. [Blacks Law 8th]