Microlith

A microlith is a small stone tool usually made of flint or chert and typically a centimetre or so in length and half a centimetre wide. They were made by people from 35,000 years ago to about 3,000 years ago, in Europe, north Africa, across Asia and in Australia, and used in spear points and arrowheads.

Microliths are produced from either a small blade (microblade) or a larger blade-like piece of flint by abrupt or truncated retouching, which leaves a very typical piece of waste, called a microburin. The microliths themselves are sufficiently worked so as to be distinguishable from workshop waste or accidents.

Two families of microliths are usually defined: laminar and geometric. An assemblage of microliths can be used to date an archeological site. Laminar microliths are associated with the end of the Upper Paleolithic and the beginning of the Epipaleolithic era; geometric microliths are characteristic of the Mesolithic and the Neolithic. Geometric microliths may be triangular, trapezoid or lunate. Microlith production generally declined following the introduction of agriculture (8000 BCE) but continued later in cultures with a deeply rooted hunting tradition.

Microlith (disambiguation)

Microlith (disambiguation) may refer to:

Microlith (catalytic reactor)

Microlith is a brand of catalytic reactor invented by the prize-winning engineer William C. Pfefferle and sold by Precision Combustion. Microlith's advantages include its weight, size, efficiency, and fast thermal response.

Technology

A catalyst is a substance that speeds a reaction but that itself is left in its original state after the reaction, so that it can assist in the reaction of a large quantity of material over a long period of time. A Microlith reactor is constructed with a very thin metal substrate coated with a variety of materials including catalysts to speed reactions, and adsorbent materials for use in filters. The substrate has short channels (0.001–0.020 in) which resemble screens or meshes. This results in a lower pressure drop than other reactors and allows for high cell density and low thermal mass. Mass and heat transfer are significantly increased, allowing faster reactor response to gas temperatures and improved rates of reactant contact with the surface. By passing an electric current through the metal substrate, the Microlith can be heated rapidly and efficiently. Over 12 Microlith related US patents have been issued.