Formative stage in the context of "Archaic Period (Americas)"

The names for archaeological periods vary enormously from region to region. This is a list of the main divisions by continent and region. Dating also varies considerably and those given are broad approximations across wide areas.

The three-age system has been used in many areas, referring to the prehistorical and historical periods identified by tool manufacture and use, of Stone Age, Bronze Age and Iron Age. Since these ages are distinguished by the development of technology, it is natural that the dates to which these refer vary in different parts of the world. In many regions, the term Stone Age is no longer used, as it has been replaced by more specific geological periods. For some regions, there is need for an intermediate Chalcolithic period between the Stone Age and Bronze Age. For cultures where indigenous metal tools were in less widespread use, other classifications, such as the lithic stage, archaic stage and formative stage refer to the development of other types of technology and social organization.

The Sierra de Los Tuxtlas (Tuxtlas Mountains) are a volcanic belt and mountain range along the southeastern Veracruz Gulf coast in Eastern Mexico. The Los Tuxtlas Biosphere Reserve (Biósfera Los Tuxtlas) includes the coastal and higher elevations of the Sierra de Los Tuxtlas.

The volcanic mountains were used as a basalt source by the Olmec culture during the Early Formative period (c. 1500 BCE – c. 400 BCE). Quarried basalt was transported by raft through a network of rivers, to sites in the Olmec heartland for use in creating monuments, including colossal heads.

In the classification of the archaeology of the Americas, the Post-Classic stage is a term applied to some pre-Columbian cultures, typically ending with local contact with Europeans. This stage is the fifth of five archaeological stages posited by Gordon Willey and Philip Phillips' 1958 book Method and Theory in American Archaeology.

1. The Lithic stage
2. The Archaic stage
3. The Formative stage
4. The Classic stage
5. The Post-Classic stage

Cultures of the Post-Classic Stage are defined distinctly by possessing developed metallurgy. Social organization is supposed to involve complex urbanism and militarism. Ideologically, Post-Classic cultures are described as showing a tendency towards the secularization of society.

Oneota is a designation archaeologists use to refer to a cultural complex that existed in the Eastern Plains and Great Lakes area of what is now occupied by the United States from around AD 900 to around 1650 or 1700. Based on the classification defined in Gordon Willey and Philip Phillips' 1958 book Method and Theory in American Archaeology, the Oneota culture belongs to formative stage. The culture is believed to have transitioned into various Siouan cultures of the protohistoric and historic times, such as the Ioway.

Oneota is considered a major component of Upper Mississippian culture. It is characterized by globular, shell-tempered pottery that is often coarse in fibre. Pieces often had a spherical body, short necks and/or a flat lip. Sometimes the vessels had strap handles. Decoration includes wavy and zigzag lines, often in parallel. Most decoration was done on the top half of the vessel. One site occupied by the Oneota people for a period was the Aztalan site beside the Crawfish river in Wisconsin.

A macuahuitl ([maːˈkʷawit͡ɬ]), plural māccuahuimeh, is a Mesoamerican weapon consisting of a wooden sword with several embedded obsidian blades. The name is derived from the Nahuatl language and means "hand-wood". Its sides are embedded with prismatic blades traditionally made from obsidian, which is capable of producing an edge sharper than high quality steel razor blades. The macuahuitl was a standard close combat weapon.

Use of the macuahuitl as a weapon is attested from the first millennium CE, although specimens can be found in art dating to at least pre-classic times. By the time of the Spanish conquest, the macuahuitl was widely distributed in Mesoamerica. The weapon was used by different civilizations, including the Aztec (Mexicas), Olmec, Maya, Mixtec, Toltec, and Tarascans.