Ocean Minerals Company (OMCO) carried out 16 expeditions to the Clarion‐Clipperton region of the northeastern tropical Pacific between 1978 and 1981. During these cruises OMCO collected substantial data through acoustic profiling, video and photographic imaging of the seabed, and sampling of the deposits with dredges, box cores, and free‐fall grab samplers. In 1990 the samples, photographs, technical reports, and computer data bases that resulted from this work were archived at the Marine Minerals Technology Center at the University of Hawaii. This examination focuses on the biological observations made from the more than 10,000 photographs of the seabed and the manganese nodule size distributions and ore‐grade data from the free‐fall grab recoveries.