1. Map showing the distribution of anomalous concentrations of copper, lead, zinc, tin, and tungsten in stream sediment and heavy-mineral concentrate in the Iditarod quadrangle, Alaska Yale Public content 1997. 2002-06-01T04:00:00Z. 2002-06-01T04:00:00Z. Geological Survey (U.S.). The Survey ; For sale by Information Services. English. Public. Alaska and Iditarod Region.