National Geographic : 1941 Nov
Staff Photographer J.Baylor Roberts Ankle-deep in Muddy Streams, Sluice Tenders Retrieve Tin Ore, Vital U. S.Defense Need Under pounding of a powerful jet of water, tin-bearing earth is broken down and washed into a basin. Then themixture ofwater, ore, sand, and dirt ispumped up to the top of these sluices and allowed to flow down. Strips across the flooring catch the heavy tin, while the lighter sand and dirt wash away. Atintervals the stream is shut off and the collected ore removed in baskets. From the Malay Archipelago comes about one-third ofthe world's supply oftin.