Númenórean brick is a block mainly used in Umbar structures, first added in Public Beta 22 as a variant of Gondor Brick. It is a stone brick block which can be crafted from Mordor Rock on any Númenórean crafting table.
Númenórean brick can be found naturally in most Umbaric structures, and crafting materials found all over Mordor.
Stairs, pillars, slabs and two carved variants can also be crafted and found naturally.
As of Public Beta 27, Gondor bricks and their black counterparts have a gulduril variant. These cannot be crafted, but are created by right-clicking their respective block with a piece of gulduril. This creates a green shimmering effect around the block, useful for buildings like Minas Morgul and other haunted-like builds.