Flint
Flint (or
flintstone) is a hard,
sedimentary cryptocrystalline silicate rock with a glassy appearance. Flint is usually dark-grey, blue, black, or deep brown in color. It occurs chiefly as
nodules and masses in sedimentary rocks, such as
chalks and
limestones.
The exact mode of formation of flint is not yet clear or agreed but it is thought that it occurs as a result of chemical changes in compressed sedimentary rock formations, during the process of
diagenesis. One theory is that a gelatinous material fills cavities in the sediment, such as holes bored by crustaceans or molluscs and that this becomes silicified. This could certainly explain the complex shapes of flint that are found.
In
Europe, some of the best
toolmaking flint has come from
Belgium (Obourg,
flint mines of
Spiennes), the coastal chalks of the
English Channel, the
Paris Basin, the Sennonian deposits of
Rügen,
Grimes Graves in England and the
Jurassic deposits of the
Kraków-area in
Poland. Flint mining is attested since the
Palaeolithic, but became more common since the
Neolithic (
Michelsberg culture,
Funnelbeaker culture).
*One of the most commonly used materials for the manufacture of
stone tools during the
Stone Age, as it splits into thin, sharp splinters called flakes or blades (depending in the shape) when struck by another hard object (such as a
hammerstone made of another material).
*When struck against steel, flint will produce sparks, which when directed onto
tinder, can be used to start a fire. This occurs when the hard flint knocks off a particle of the steel, which is heated by the impact, and then burns with oxygen from the atmosphere. This method is popular in
woodcraft and among
campers who want to have an 'authentic' experience. Striking a lump of flint against a piece of steel to make fire is not particularly easy or convenient (although it is much easier than other primitive fire-making methods such as using a
bow and drill). Because of this, a
similar technology has been miniaturized and integrated into
lighters, which are easy to use without skill or practise.
*Starting a fire with flint is a staple of
scouting lore, probably because scouting started in England, where natural flint can be found in many places. In North America, however, where woodcraft is quite popular, most scouts have never seen natural flint.
*A later major use was to create the spark that would ignite the powder that would fire a ball or bullet from a
flintlock firearm. While the military use of a flintlock declined after the British military generally applied the percussion cap on their muskets in
1842, it is still popular to use the flintlock as a hunting rifle during special muzzleloader seasons or general rifle seasons in several states in the US.
*Flint was used extensively from the
13th century until the present day as a material for building stone walls, especially in parts of
England. In chalky coastal areas of England flint has also been used as a building and walling material, predating the common use of bricks but laid in a similar manner, using lime mortar. For instance, flint was used in the construction of many churches and other buildings in
East Anglia.
*Flint pebbles are used as the media in ball mills to grind glazes and other raw materials for the ceramics industry. The pebbles are hand-selected for colour, with those showing a reddish tint, indicating the presence of iron, being discarded. The remaining blue-grey stones have a low content of chromophoric oxides and so should impart lesser amounts of colouring contaminants.
*In England flint pebbles were traditionally an important raw material for clay based
ceramic bodies; after high temperature treatment, to remove organic impurites and induce certain physical reactions, calcined flint performed a similar role to quartz sand used in other countries, i.e. after milling to fine particle size was the filler component in
pottery bodies. Because of this historical use American potters now, erroneously, refer to all siliceous fillers as flint.
*
Chalcedony*
Chert*
Eolith*
Obsidian*
List of minerals*
Ferrocerium, an alloy also referred to as "flint"
*
Grimes Graves, a prehistoric flint mine in
Norfolk,
England*
Flint vs Chert Authentic Artefacts Collectors Assn.*
General quartz & silica ref.*
Flintsource.net European Artefacts - detailed site*
Flint and steel clarifications
