Each Agate Coffee Table by Phillips Collection is a one of a kind jewel of nature's creation. As tectonic lava churns, gas bubbles form and create small caverns within the lava. As the hollow caverns push towards the surface, they are filled with various fluids which in turn solidify layer by layer. Eventually this process forms an agate, each with the unique and beautiful colors and rings you see in the cut and polished pieces. Each gemstone is individually selected, polished, and placed to crate this truly amazing functional piece of art. The top rests upon a stainless steel base.