Assertion: clay roofing tile | /r/CapableOf | create with copper slag
Facets:
value: usually
type: TEMPORAL
Source sentences:
text: Most historic glazed roofing tiles are in fairly natural hues that range from reds and browns and buffs, to blacks and purples, blues (often created with smalt, or powdered blue glass), and a wide variety of greens (usually created with copper slag).