In maritime law, flotsam, jetsam, lagan and derelict refer to specific kinds of items found at sea. Unrecovered, unreturned pays homage to those things lost forever on and in the vastness of the ocean.
Flotsam- goods from a sunken vessel that float on the surface of the sea, or any floating cargo that is cast overboard as a result of an accident. Ownership is attributed to whoever recovers the items unless someone steps forward and can prove ownership.
Jetsam- refers to any cargo that is intentionally discarded from a ship or wreckage. Jetsam can be claimed by whoever recovers it.
Lagan- goods that are cast overboard and sink, but are attached to a floating marker and therefore marked. Lagan must be returned to the rightful owner upon discovery.
Derelict- goods that have sunk, given up by the owner. In other words, goods with no hope of being recovered or returned, regardless of the means of abandonment (ie. purposeful or forced).