Third phase in the development of material culture among the ancient peoples of Europe, Asia, and the Middle East, following the Paleolithic and Neolithic periods and preceding the Iron Age. The term also denotes the first period in which metal was used. The date at which the age began varied by region; in Greece and China it began before 3000 BC, in Britain not until c. 1900 BC. The beginning of the period is sometimes called the Chalcolithic (Copper-Stone) Age, referring to the initial use of pure copper (along with its predecessor, stone). By 3000 BC the use of copper was well known in the Middle East, had extended westward into the Mediterranean area, and was beginning to infiltrate Europe. Only in the 2nd millennium BC did true bronze come to be widely used. The age was marked by increased specialization and the invention of the wheel and the ox-drawn plow. From c. 1000 BC the ability to heat and forge iron brought the Bronze Age to an end.