The first investigation into the ultraviolet (UV) photoluminescence of gadolinium(III) in the presence of copper(II) is reported. A melt-quenched barium phosphate glass was used as a model matrix. The optical spectroscopy assessment shows that with increasing CuO concentration the Cu(2+) absorption band grows steadily, whereas the UV emission from Gd(3+) ions is progressively quenched. The data, thus, suggests the existence of a Gd(3+) →Cu(2+) energy-transfer process ocurring through quantum cutting. A downconversion/cross-relaxation pathway proceeding through a virtual state in Gd(3+) is proposed. These findings suggest gadolinium(III) could potentially be used in the optical sensing of copper(II).