Onyx Black Is a unique Italian black porcelain slab designed to give any interior or exterior space flare. This 12mm polished porcelain features a deep black background with soft and brushed storm-like veins. Porcelain slabs are thinner, easier to install on large fireplaces, wall-clad, collumns, stone walls and is the preffered outdoor stone. Black porcelain is offered as large format tile and are book-matched to create stunning waterfall edges, matching/mirroring slab walls.