Tuff, Tuff stairs, tuff slabs, tuff walls, Chesiled tuff, polished tuff, polished tuff stairs, polished tuff slabs, polished tuff wall, tuff bricks, tuff brick stairs, tuff brick slab, tuff brick wall, and chiseled tuff bricks are all in the Nature category in the creative inventory instead of in their respective sub-categories.

The tuff wall, polished tuff wall, and tuff brick wall should be in the Walls sub-category in Construction.
The tuff slab, polished tuff slab, and tuff brick slab should be in the slab sub-category in Construction.
The tuff stairs, polished tuff stairs, and tuff brick stairs should be in the Stairs sub-category in Construction.
Tuff and polished tuff should be in the stone sub-category in Nature.
Tuff bricks, chiseled tuff, and chiseled tuff bricks should be in the Decorative Stone sub-category in Construction.