Lithic core in the context of "Archaeological industry"

In archaeology, in particular of the Stone Age, lithic reduction is the process of fashioning stones or rocks from their natural state into tools or weapons by removing some parts. It has been intensely studied and many archaeological industries are identified almost entirely by the lithic analysis of the precise style of their tools and the chaîne opératoire of the reduction techniques they used.

Normally the starting point is the selection of a piece of tool stone that has been detached by natural geological processes, and is an appropriate size and shape. In some cases solid rock or larger boulders may be quarried and broken into suitable smaller pieces, and in others the starting point may be a piece of the debitage, a flake removed from a previous operation to make a larger tool. The selected piece is called the lithic core (also known as the "objective piece"). A basic distinction is that between flaked or knapped stone, the main subject here, and ground stone objects made by grinding. Flaked stone reduction involves the use of a hard hammer percussor, such as a hammerstone, a soft hammer fabricator (made of wood, bone or antler), or a wood or antler punch to detach lithic flakes from the lithic core. As flakes are detached in sequence, the original mass of stone is reduced; hence the term for this process. Lithic reduction may be performed in order to obtain sharp flakes, of which a variety of tools can be made, or to rough out a blank for later refinement into a projectile point, knife, or other object. Flakes of regular size that are at least twice as long as they are broad are called blades. Lithic tools produced this way may be bifacial (exhibiting flaking on both sides) or unifacial (exhibiting flaking on one side only).

In archaeology, a blade is a type of stone tool created by striking a long narrow flake from a stone core. This process of reducing the stone and producing the blades is called lithic reduction. Archaeologists use this process of flintknapping to analyze blades and observe their technological uses for historical purposes.

Blades are defined as being flakes that are at least twice as long as they are wide and that have parallel or subparallel sides and at least two ridges on the dorsal (outer) side. Blade cores appear and are different from regular flaking cores, as each core's conchoidal nature is suited for different types of flaking. Blades are created using stones that have a cryptocrystalline structure and easily be fractured into a smooth piece without fracturing. Blades became the favored technology of the Upper Palaeolithic era, although they are occasionally found in earlier periods. Different techniques are also required for blade creation; a soft punch or hammerstone is necessary for creating a blade.

Kenyanthropus ('man from Kenya') is a genus of extinct hominin identified from the Lomekwi site by Lake Turkana, Kenya, dated to 3.3 to 3.2 million years ago during the Middle Pliocene. It contains one species, K. platyops, but may also include the two-million-year-old Homo rudolfensis, or K. rudolfensis. Before its naming in 2001, Australopithecus afarensis was widely regarded as the only australopithecine to exist during the Middle Pliocene, but Kenyanthropus evinces a greater diversity than once acknowledged. Kenyanthropus is most recognisable by an unusually flat face and small teeth for such an early hominin, with values on the extremes or beyond the range of variation for australopithecines in regard to these features. Multiple australopithecine species may have coexisted by foraging for different food items (niche partitioning), which may be the reason why these apes anatomically differ in features related to chewing.

The Lomekwi site also yielded the earliest stone tool industry, the Lomekwian, characterised by the rudimentary production of simple flakes by pounding a core against an anvil or with a hammerstone. It may have been manufactured by Kenyanthropus, but it is unclear if multiple species were present at the site or not. The knappers were using volcanic rocks collected no more than 100 m (330 ft) from the site. Kenyanthropus seems to have lived on a lakeside or floodplain environment featuring forests and grasslands.

In the archaeology of the Stone Age, an industry or technocomplex is a typological classification of stone tools.

An industry consists of a number of lithic assemblages, typically including a range of different types of tools, that are grouped together on the basis of shared technological or morphological characteristics. For example, the Acheulean industry includes hand-axes, cleavers, scrapers and other tools with different forms, but which were all manufactured by the symmetrical reduction of a bifacial core producing large flakes. Industries are usually named after a type site where these characteristics were first observed (e.g. the Mousterian industry is named after the site of Le Moustier). By contrast, Neolithic axeheads from the Langdale axe industry were recognised as a type well before the centre at Great Langdale was identified by finds of debitage and other remains of the production, and confirmed by petrography (geological analysis). The stone was quarried and rough axe heads were produced there, to be more finely worked and polished elsewhere.

The Levallois technique (IPA: [lə.va.lwa]) is a name given by archaeologists to a distinctive type of stone knapping developed around 250,000 to 400,000 years ago during the Middle Palaeolithic period. It is part of the Mousterian stone tool industry, and was used by the Neanderthals in Europe and by modern humans in other regions such as the Levant.

It is named after 19th-century finds of flint tools in the Levallois-Perret suburb of Paris, France. The technique was more sophisticated than earlier methods of lithic reduction, involving the striking of lithic flakes from a prepared lithic core. A striking platform is formed at one end and then the core's edges are trimmed by flaking off pieces around the outline of the intended lithic flake. This creates a domed shape on the side of the core, known as a tortoise core, as the various scars and rounded form are reminiscent of a tortoise's shell. When the striking platform is finally hit, a lithic flake separates from the lithic core with a distinctive plano-convex profile and with all of its edges sharpened by the earlier trimming work.

In archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure," and may also be referred to as simply a flake, or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core. Once the proper tool stone has been selected, a percussor or pressure flaker (e.g., an antler tine) is used to direct a sharp blow, or apply sufficient force, respectively, to the surface of the stone, often on the edge of the piece. The energy of this blow propagates through the material, often (but not always) producing a Hertzian cone of force which causes the rock to fracture in a controllable fashion. Since cores are often struck on an edge with a suitable angle (<90°) for flake propagation, the result is that only a portion of the Hertzian cone is created. The process continues as the flintknapper detaches the desired number of flakes from the core, which is marked with the negative scars of these removals. The surface area of the core which received the blows necessary for detaching the flakes is referred to as the striking platform.