The YCuO2 and LaCuO2 delafossites consist of alternating triangular planes of Ln3+ octahedra and O-Cu1+-O sticks. Here it is shown that under a limited set of conditions they may be oxidized to form new delafossite-derived phases YCuO2.5+x, 0 ≤ x ≤ 0.05, and LaCuO25+x, 0.07 ≤ x ≤ 0.18. Electron microscopy and powder X-ray diffraction are employed to characterize the resulting structures. Temperature-dependent resistivities and magnetic susceptibilities are reported. Characterization by soft X-ray photoabsorbtion spectroscopy, which shows them to be electronically unlike cuprates such as La2-xSrxCuO4, is also reported.