Scoria

·noun Cellular slaggy lava; volcanic cinders.

II. Scoria ·noun The recrement of metals in fusion, or the slag rejected after the reduction of metallic ores; dross.

scoria
scōrĭa, ae, f., = σκωρία, dross , slag , scoria of metals, Plin. 33, 4, 21, § 69; 33, 6, 35, § ...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.