Abstract Wyandotte Cave (Figs. 1,2) is a large limestone cave system in southern Indiana. From archaeological investigations in the cave, we know that several of the aragonite formations were quarried by prehistoric people. We also know, based on examination of curated collections, that some artifacts recovered from prehistoric archaeological sites in eastern North America are made from materials similar to the Wyandotte Cave aragonite. In this chapter the mineralogical and chemical characteristics of speleothem aragonite from Wyandotte Cave and other locales are described. Some of the characteristics of Wyandotte aragonite are distinctive, and therefore can serve as "fingerprints." When these are found in artifacts they are evidence that the source of the raw material was Wyandotte Cave, Indiana.