Metamorphic rock
Uses

Slate tiles are used in construction, particularly as roof shingle.

Quartzite is sufficiently hard and dense that it is difficult to quarry. However, some quartzite is used as dimension stone, often as slabs for flooring, walls, or stairsteps. About 6% of crushed stone, used mostly for road aggregate, is quartzite.

Marble is also prized for building construction and as a medium for sculpture.
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