Natural Stone is a solid composite of one or more natural minerals which combine in a complex geological process to form one of the three major groups of stone defined as Igneous, Sedimentary and Metamorphic. In the world of Architecture and Construction PBM partners with quarries from around the world to bring these materials to our 5 locations in the Bay Area; Flagstone, Cut/Dimensional Paving, Full Stone, Thin Veneer, Caps/Sills/Treads and various other products.Come, Explore, Discover.