We have measured multi-keV protons and ∼100 keV iodine ions from the interaction of intense, femtosecond laser pulses with atomic Xe clusters and mixed-species HI clusters. The explosion dynamics of the HI clusters differs from the pure H and I cluster cases, with the iodine energies being substantially reduced. Mixed-species clusters provide a possible route for boosting the explosion energies of low-Z ions, and extend the advantages of the laser-cluster interaction to species that do not readily form pure clusters.