The surfaces are composed of layers of paint that have dried to create vibrating optical effects. To create his works, Beltrán produces custom molds and pours paint into them, allowing the paint to harden and dry over time. The artist sometimes integrates objects into his moulds — such as leftover materials or detritus from his studio — to introduce “interruptions” into his compositions. He repeats this process for months or even years, as layers of paint coagulate and accumulate. The artist then removes the mold and slices the resulting object — a hardened block with swirls and layers of color — into strips using a custom-built machine. The strips are then arranged in bold, planar compositions, which he adheres to a wooden substrate.