Lithic reduction involves the use of a hard hammer precursor, 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 a lump of
tool stone called a
lithic core (also known as the "objective piece"). 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, on 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).
Removed flakes exhibit features characteristic of conchoidal fracturing, including striking platforms, bulbs of force, and occasionally eraillures (small secondary flakes detached from the flake's bulb of force). Flakes are often quite sharp, with distal edges only a few molecules thick, and can be used directly as tools or modified into other utilitarian implements, such as spokeshaves and scrapers.
Percussion reduction, or percussion flaking, refers to removal of flakes by striking a core or other objective piece, such as a partially formed tool, with a hammer or percussor. Alternatively, the objective piece can also be struck against a stationary anvil-stone, known as bipolar percussion. Percussors are traditionally either a stone cobble or pebble, often referred to as a hammerstone, or a billet made of bone, antler, or wood. Often, flakes are struck from a core using a punch, in which case the percussor never actually makes contact with the objective piece. This technique is referred to as indirect percussion. (Andrefsky 200412)
Hard hammer techniques are generally used to remove large flakes of stone. Early flintknappers and hobbyists replicating their methods often use cobbles of very hard stone, such as quartzite. This technique can be used by flintknappers to remove broad flakes that can be made into smaller tools. This method of manufacture is believed to have been used to make some of the earliest stone tools ever found, some of which date from over 2 million years ago.
