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n. Geology Porous cinderlike fragments of dark lava. Also called cinders, slag.

n. Metallurgy The refuse of a smelted metal or ore; slag. Also called cinder.

n. The recrement of metals in fusion, or the slag rejected after the reduction of metallic ores; dross.

n. Cellular slaggy lava; volcanic cinders.

n. Dross; cinder; slag: a word of rather variable and indefinite meaning, generally used in the plural, and with reference to volcanic rocks. See scoriaceous.

n. A genus of geometrid moths, containing such as the black-veined moth, S. dealbata.

n. the scum formed by oxidation at the surface of molten metals

"From the observatory, where His Majesty's faithful servant still remains, come telegrams that the great pebbles -- what we call scoria -- have ruined"

thread-lace scoria   

scoriae   

scoriac    scoriation    scorification    scorified    scoriaceous    scorify    scoriated    scoriform    scorifier   

dross   

clinkers    scoriae    pumice    tufa    syenite    clinker    adiamante    slag    5    lapilli