This data release compiles element composition data for more than 600 deep-ocean mineral samples from more than 25 research cruises in the Pacific Ocean since 1979 that involved USGS researchers. Deep-ocean mineral sample types encompassed in this data release include ferromanganese crusts, manganese nodules, phosphorites, and hydrothermal minerals. This data release is comprised of both unpublished as well as previously published data and reports and includes analytical methods and instrument detection ...