The interaction between 258, 350, and 910 MeV 'He ions and natural copper has been studied by measuring radiochemical cross sections and thick target/thick catcher recoil properties of a number of produced radionuclides. Absolute cross sections are obtained at 350 and 910 MeV, only relative cross sections at 258 MeV. Integration of the obtained mass yield curves gives 1467 mb for the total spallation cross section both for 350 and 910 MeV 3 He ions.The recoil data has been analyzed with the two-step vector model to deduce momentum transfers and product kinetic energies.The cross sections and the deduced energies and velocities are compared with Monte Carlo cascade-evaporation calculations. This comparison gives agreement varying from fair for cross sections to excellent for momentum transfers and excitation energies.We suggest that the deduced kinetic energies for spallation products to a very large extent are due to the distributions of the perpendicular and parallel velocities imparted to the target in the cascade step. Taking these distributions into account, the Monte Carlo calculations reproduce perfectly the energies deduced from the experimental data.A collection of deduced cascade residual velocities and excitation energies for reactions between copper and 150-800 MeV protons, 1-4.8 GeV "Cand 258-910 MeV 3 He indicates that the main primary interaction is identical for all these particles.