Assertion: slate | /r/ObjectUse | used on roof
Facets:
value: mainly
type: DEGREE
value: for hundreds of years
type: TEMPORAL
Source sentences:
text: Slate is a type of rock which has been used on floors and roofs for hundreds of years.
text: The type of slate used for roofing and hearths is chosen for its ability to withstand temperature changes.
text: Mr. Jenkins explained that while there are a variety of sizes, shapes, colors and styles of slate used on roofs, most slate roofs can be divided into two basic categories: hard and soft.
text: Slate is mainly used for roofing, but is also produced as thicker slab for a variety of uses including flooring, worktops and headstones.