Franco Costalonga's "OC GBMN" from 2004 presents a compelling quartet of optical explorations, meticulously arranged within a precise grid format. Each of the four compositions features a vibrant, sculpted element encased beneath a clear plexiglass hemisphere, set against a deep black ground that intensifies the colors. Two of these internal forms glow in a striking lime green, while the others radiate in a rich blue and a vivid red. These hourglass-like structures possess a unique, almost flocked texture, creating a soft, light-absorbing contrast to the highly reflective, polished surfaces of their transparent enclosures. The interplay of light, reflection, and shadow across the curved plexiglass introduces a dynamic visual experience, constantly shifting as the viewer's perspective changes. This work exemplifies Costalonga's profound engagement with the principles of optical and kinetic art, a legacy he advanced through innovative material use. The choice of plexiglass is not merely functional; it is integral to the artwork's conceptual core, allowing for intricate plays of light and distorted reflections that challenge conventional perception. The precise, almost industrial aesthetic of the black boxes and clear domes frames the organic, tactile quality of the internal colored forms, creating a captivating tension. "OC GBMN" invites prolonged contemplation, revealing new visual nuances with each viewing, a testament to Costalonga's mastery in crafting objects that transcend mere form to become active participants in the viewer's optical experience. This piece stands as a sophisticated example of his enduring contribution to art that engages both the eye and the intellect.