The Index to Marine and Lacustrine Geological Samples (IMLGS) describes and provides access to ocean floor and lakebed rock and sediment samples curated by participating institutional and government repositories in the U.S., Canada, the United Kingdom, France, and Germany. Each curatorial facility prepares data on their own collection for the IMLGS. Data include basic collection and storage information. Lithology, texture, age, principal investigator, province, weathering, metamorphism, glass remarks, and descriptive data are included for some samples, at the discretion of the curator. The Index provides links to view and download related data and images in the long-term archive, at participating institutions.