Three age system

Three Age system
(thrē)
A system for classifying prehistoric artifacts according to successive stages of technological development, divided into the Stone, Bronze, and Iron ages.

Our Living Language : In organizing the extensive collection of artifacts at the National Museum of Denmark, the 19th-century Danish archaeologist Christian Thomsen proposed an innovative system based on the assumption of a progression in human technology from stone to bronze to iron. His insight that early technology had developed in chronological stages, rather than concurrently at different levels of society, proved essentially correct, though ultimately of limited use in describing the various progressions in parts of the world other than Europe, western Asia, and northern Africa. Once empirical study of archaeological collections began, Thomsen’s Three Age system was rapidly modifed into four ages by the subdivision of the Stone Age into the Old Stone (now Paleolithic) and New Stone (Neolithic) ages. Subsequent refinement has added Mesolithic (Middle Stone) and Chalcolithic (Copper and Stone) to the original terms, which are now known as periods rather than ages. Use of the full terminology—Paleolithic, Mesolithic, Neolithic, Chalcolithic, Bronze, and Iron—is appropriate only for Europe, the Middle East, and Egypt, and even there it is not uniformly accepted among archaeologists today.