peperite
/ˈpɛpərʌɪt/Geology rare before 20th cent
noun
A brecciated volcanic material in marine sedimentary rock, regarded by some as being formed by the intrusion of lava or magma into sediment under water, and by others as a product of the mixing of volcanic ejecta with such sediments.
Origin
Mid 19th century; earliest use found in The Civil Engineer and Architect's Journal. From peper- + -ite, after French pépérite.