Chert
Chert is a hard, fine-grained sedimentary rock composed of crystals of quartz that are small. Quartz is the mineral form of silicon dioxide. Chert is of biological origin but may occur inorganically as a chemical precipitate or a diagenetic replacement. Geologists use chert as a generic name for any type of cryptocrystalline quartz. Chert is of biological origin, being the petrified remains of siliceous ooze, the biogenic sediment that covers large areas of the deep ocean floor, which contains the silicon skeletal remains of diatoms, silicoflagellates, radiolarians. Depending on its origin, it can contain small macrofossils, or both, it varies in color, but most manifests as gray, grayish brown and light green to rusty red. Chert occurs in carbonate rocks as oval to irregular nodules in greensand, limestone and dolostone formations as a replacement mineral, where it is formed as a result of some type of diagenesis. Where it occurs in chalk or marl, it is called flint, it occurs in thin beds, when it is a primary deposit.
Thick beds of chert occur in deep marine deposits. These thickly bedded cherts include the novaculite of the Ouachita Mountains of Arkansas and similar occurrences in Texas and South Carolina in the United States; the banded iron formations of Precambrian age are composed of alternating layers of chert and iron oxides. Chert occurs in diatomaceous deposits and is known as diatomaceous chert. Diatomaceous chert consists of beds and lenses of diatomite which were converted during diagenesis into dense, hard chert. Beds of marine diatomaceous chert comprising strata several hundred meters thick have been reported from sedimentary sequences such as the Miocene Monterey Formation of California and occur in rocks as old as the Cretaceous. In petrology the term "chert" is used to refer to all rocks composed of microcrystalline, cryptocrystalline and microfibrous quartz; the term does not include quartzite. Chalcedony is a microfibrous variety of quartz. Speaking, the term "flint" is reserved for varieties of chert which occur in chalk and marly limestone formations.
Among non-geologists, the distinction between "flint" and "chert" is one of quality – chert being lower quality than flint. This usage of the terminology is prevalent in North America and is caused by early immigrants who brought the terms from England where most true flint was indeed of better quality than "common chert". Among petrologists, chalcedony is sometimes considered separately from chert due to its fibrous structure. Since many cherts contain both microcrystalline and microfibrous quartz, it is sometimes difficult to classify a rock as chalcedony, thus its general inclusion as a variety of chert; the cryptocrystalline nature of chert, combined with its above average ability to resist weathering, recrystallization and metamorphism has made it an ideal rock for preservation of early life forms. For example: The 3.2 Ga chert of the Fig Tree Formation in the Barbeton Mountains between Swaziland and South Africa preserved non-colonial unicellular bacteria-like fossils. The Gunflint Chert of western Ontario preserves not only bacteria and cyanobacteria but organisms believed to be ammonia-consuming and some that resemble green algae and fungus-like organisms.
The Apex Chert of the Pilbara craton, Australia preserved eleven taxa of prokaryotes. The Bitter Springs Formation of the Amadeus Basin, Central Australia, preserves 850 Ma cyanobacteria and algae; the Rhynie chert of Scotland has remains of a Devonian land flora and fauna with preservation so perfect that it allows cellular studies of the fossils. In prehistoric times, chert was used as a raw material for the construction of stone tools. Like obsidian, as well as some rhyolites, felsites and other tool stones used in lithic reduction, chert fractures in a Hertzian cone when struck with sufficient force; this results in a characteristic of all minerals with no cleavage planes. In this kind of fracture, a cone of force propagates through the material from the point of impact removing a full or partial cone; the partial Hertzian cones produced during lithic reduction are called flakes, exhibit features characteristic of this sort of breakage, including striking platforms, bulbs of force, eraillures, which are small secondary flakes detached from the flake's bulb of force.
When a chert stone is struck against an iron-bearing surface sparks result. This makes chert an excellent tool for starting fires, both flint and common chert were used in various types of fire-starting tools, such as tinderboxes, throughout history. A primary historic use of common chert and flint was for flintlock firearms, in which the chert striking a metal plate produces a spark that ignites a small reservoir containing black powder, discharging the firearm. Cherts are subject to problems. Weathered chert develops surface pop-outs when used in concrete that undergoes freezing and thawing because of the high porosity of weathered cher
Quartzite
Quartzite is a hard, non-foliated metamorphic rock, pure quartz sandstone. Sandstone is converted into quartzite through heating and pressure related to tectonic compression within orogenic belts. Pure quartzite is white to grey, though quartzites occur in various shades of pink and red due to varying amounts of iron oxide. Other colors, such as yellow, green and orange, are due to other minerals; when sandstone is cemented to quartzite, the individual quartz grains recrystallize along with the former cementing material to form an interlocking mosaic of quartz crystals. Most or all of the original texture and sedimentary structures of the sandstone are erased by the metamorphism; the grainy, sandpaper-like surface becomes glassy in appearance. Minor amounts of former cementing materials, iron oxide, silica and clay migrate during recrystallization and metamorphosis; this causes lenses to form within the quartzite. Orthoquartzite is a pure quartz sandstone composed of well-rounded quartz grains cemented by silica.
Orthoquartzite is 99% SiO2 with only minor amounts of iron oxide and trace resistant minerals such as zircon and magnetite. Although few fossils are present, the original texture and sedimentary structures are preserved; the term is traditionally used for quartz-cemented quartz arenites, both usages are found in the literature. The typical distinction between the two is a metamorphic quartzite is so cemented, diagenetically altered, metamorphosized so that it will fracture and break across grain boundaries, not around them. Quartzite is resistant to chemical weathering and forms ridges and resistant hilltops; the nearly pure silica content of the rock provides little material for soil. In the United States, formations of quartzite can be found in some parts of Pennsylvania, the Washington DC area, eastern South Dakota, Central Texas, southwest Minnesota, Devil's Lake State Park in the Baraboo Range in Wisconsin, the Wasatch Range in Utah, near Salt Lake City, Utah and as resistant ridges in the Appalachians and other mountain regions.
Quartzite is found in the Morenci Copper Mine in Arizona. The town of Quartzsite in western Arizona derives its name from the quartzites in the nearby mountains in both Arizona and Southeastern California. A glassy vitreous quartzite has been described from the Belt Supergroup in the Coeur d’Alene district of northern Idaho. In the United Kingdom, a craggy ridge of quartzite called the Stiperstones runs parallel with the Pontesford-Linley fault, 6 km north-west of the Long Mynd in south Shropshire. To be found in England are the Cambrian "Wrekin quartzite", the Cambrian "Hartshill quartzite". In Wales, Holyhead mountain and most of Holy island off Anglesey sport excellent Precambrian quartzite crags and cliffs. In the Scottish Highlands, several mountains composed of Cambrian quartzite can be found in the far north-west Moine Thrust Belt running in a narrow band from Loch Eriboll in a south-westerly direction to Skye. In Ireland areas of quartzite are found across the northwest, with Errigal in Donegal as the most prominent outcrop.
In continental Europe, various regionally isolated quartzite deposits exist at surface level in a belt from the Rhenish Massif and the German Central Highlands into the Western Czech Republic, for example in the Taunus and Harz mountains. In Poland quartzite deposits at surface level exists in Świętokrzyskie Mountains. In Canada, the La Cloche Mountains in Ontario are composed of white quartzite; the highest mountain in Mozambique, Monte Binga, as well as the rest of the surrounding Chimanimani Plateau are composed of hard, pale grey, Precambrian quartzite. Quartzite is mined in Brazil for use in kitchen countertops; because of its hardness and angular shape, crushed quartzite is used as railway ballast. Quartzite is a decorative stone and may be used to cover walls, as roofing tiles, as flooring, stair steps, its use for countertops in kitchens is expanding rapidly. It is more resistant to stains than granite. Crushed quartzite is sometimes used in road construction. High purity quartzite is used to produce ferrosilicon, industrial silica sand and silicon carbide.
During the Paleolithic, quartzite was used, along with flint and other lithic raw materials, for making stone tools. The term quartzite is derived from German: Quarzit. Neomorphism R. V. Dietrich's GemRocks: Quartzite CSU Pomona Geology: Quartzite Cowen's "The First Geologists" Minnesota Department of Natural Resources: Natural History: Minnesota's geology Wisconsin's Baraboo Syncline South Dakota 2002 Mineral Summary: Production and Environmental Issues Big Sioux River: History of Sioux Falls and Quartzite Photos
Sandstone
Sandstone is a clastic sedimentary rock composed of sand-sized mineral particles or rock fragments. Most sandstone is composed of quartz or feldspar because they are the most resistant minerals to weathering processes at the Earth's surface, as seen in Bowen's reaction series. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, yellow, grey, pink and black. Since sandstone beds form visible cliffs and other topographic features, certain colors of sandstone have been identified with certain regions. Rock formations that are composed of sandstone allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs. Fine-grained aquifers, such as sandstones, are better able to filter out pollutants from the surface than are rocks with cracks and crevices, such as limestone or other rocks fractured by seismic activity. Quartz-bearing sandstone can be changed into quartzite through metamorphism related to tectonic compression within orogenic belts.
Sandstones are clastic in origin. They are formed from cemented grains that may either be fragments of a pre-existing rock or be mono-minerallic crystals; the cements binding these grains together are calcite and silica. Grain sizes in sands are defined within the range of 0.0625 mm to 2 mm. Clays and sediments with smaller grain sizes not visible with the naked eye, including siltstones and shales, are called argillaceous sediments; the formation of sandstone involves two principal stages. First, a layer or layers of sand accumulates as the result of sedimentation, either from water or from air. Sedimentation occurs by the sand settling out from suspension. Once it has accumulated, the sand becomes sandstone when it is compacted by the pressure of overlying deposits and cemented by the precipitation of minerals within the pore spaces between sand grains; the most common cementing materials are silica and calcium carbonate, which are derived either from dissolution or from alteration of the sand after it was buried.
Colors will be tan or yellow. A predominant additional colourant in the southwestern United States is iron oxide, which imparts reddish tints ranging from pink to dark red, with additional manganese imparting a purplish hue. Red sandstones are seen in the Southwest and West of Britain, as well as central Europe and Mongolia; the regularity of the latter favours use as a source for masonry, either as a primary building material or as a facing stone, over other forms of construction. The environment where it is deposited is crucial in determining the characteristics of the resulting sandstone, which, in finer detail, include its grain size and composition and, in more general detail, include the rock geometry and sedimentary structures. Principal environments of deposition may be split between terrestrial and marine, as illustrated by the following broad groupings: Terrestrial environmentsRivers Alluvial fans Glacial outwash Lakes Deserts Marine environmentsDeltas Beach and shoreface sands Tidal flats Offshore bars and sand waves Storm deposits Turbidites Framework grains are sand-sized detrital fragments that make up the bulk of a sandstone.
These grains can be classified into several different categories based on their mineral composition: Quartz framework grains are the dominant minerals in most clastic sedimentary rocks. These physical properties allow the quartz grains to survive multiple recycling events, while allowing the grains to display some degree of rounding. Quartz grains evolve from plutonic rock, which are felsic in origin and from older sandstones that have been recycled. Feldspathic framework grains are the second most abundant mineral in sandstones. Feldspar can be divided into two smaller subdivisions: plagioclase feldspars; the different types of feldspar can be distinguished under a petrographic microscope. Below is a description of the different types of feldspar. Alkali feldspar is a group of minerals in which the chemical composition of the mineral can range from KAlSi3O8 to NaAlSi3O8, this represents a complete solid solution. Plagioclase feldspar is a complex group of solid solution minerals that range in composition from NaAlSi3O8 to CaAl2Si2O8.
Lithic framework grains are pieces of ancient source rock that have yet to weather away to individual mineral grains, called lithic fragments or clasts. Lithic fragments can be any fine-grained or coarse-grained igneous, metamorphic, or sedimentary rock, although the most common lithic fragments found in sedimentary rocks are clasts of volcanic rocks. Accessory minerals are all other mineral grains in a sandstone. Common accessory minerals include micas, olivine and corundum. Many of these accessory grains are more dense than the silicates that
Three-age system
The three-age system is the categorization of history into time periods divisible by three. In history and physical anthropology, the three-age system is a methodological concept adopted during the 19th century by which artifacts and events of late prehistory and early history could be ordered into a recognizable chronology, it was developed by C. J. Thomsen, director of the Royal Museum of Nordic Antiquities, Copenhagen, as a means to classify the museum’s collections according to whether the artifacts were made of stone, bronze, or iron; the system first appealed to British researchers working in the science of ethnology who adopted it to establish race sequences for Britain's past based on cranial types. Although the craniological ethnology that formed its first scholarly context holds no scientific value, the relative chronology of the Stone Age, the Bronze Age and the Iron Age is still in use in a general public context, the three ages remain the underpinning of prehistoric chronology for Europe, the Mediterranean world and the Near East.
The structure reflects the cultural and historical background of Mediterranean Europe and the Middle East and soon underwent further subdivisions, including the 1865 partitioning of the Stone Age into Paleolithic and Neolithic periods by John Lubbock. It is, however, of little or no use for the establishment of chronological frameworks in sub-Saharan Africa, much of Asia, the Americas and some other areas and has little importance in contemporary archaeological or anthropological discussion for these regions; the concept of dividing pre-historical ages into systems based on metals extends far back in European history originated by Lucretius in the first century BC. But the present archaeological system of the three main ages—stone and iron—originates with the Danish archaeologist Christian Jürgensen Thomsen, who placed the system on a more scientific basis by typological and chronological studies, at first, of tools and other artifacts present in the Museum of Northern Antiquities in Copenhagen.
He used artifacts and the excavation reports published or sent to him by Danish archaeologists who were doing controlled excavations. His position as curator of the museum gave him enough visibility to become influential on Danish archaeology. A well-known and well-liked figure, he explained his system in person to visitors at the museum, many of them professional archaeologists. In his poem and Days, the ancient Greek poet Hesiod between 750 and 650 BC, defined five successive Ages of Man: 1. Golden, 2. Silver, 3. Bronze, 4. Heroic and 5. Iron. Only the Bronze Age and the Iron Age are based on the use of metal:... Zeus the father created the third generation of mortals, the age of bronze... They were terrible and strong, the ghastly action of Ares was theirs, violence.... The weapons of these men were bronze, of bronze their houses, they worked as bronzesmiths. There was not yet any black iron. Hesiod knew from the traditional poetry, such as the Iliad, the heirloom bronze artifacts that abounded in Greek society, that before the use of iron to make tools and weapons, bronze had been the preferred material and iron was not smelted at all.
He did not continue the manufacturing metaphor, but mixed his metaphors, switching over to the market value of each metal. Iron was cheaper than bronze, so there must have been a silver age, he portrays a sequence of metallic ages. Each age has less of a moral value than the preceding. Of his own age he says: "And I wish that I were not any part of the fifth generation of men, but had died before it came, or had been born afterward." The moral metaphor of the ages of metals continued. Lucretius, replaced moral degradation with the concept of progress, which he conceived to be like the growth of an individual human being; the concept is evolutionary:. Everything must pass through successive phases. Nothing remains. Everything is on the move. Everything is transformed by nature and forced into new paths... The Earth passes through successive phases, so that it can no longer bear what it could, it can now what it could not before; the Romans believed that the species of animals, including humans, were spontaneously generated from the materials of the Earth, because of which the Latin word mater, "mother", descends to English-speakers as matter and material.
In Lucretius the Earth is Venus, to whom the poem is dedicated in the first few lines. She brought forth humankind by spontaneous generation. Having been given birth as a species, humans must grow to maturity by analogy with the individual; the different phases of their collective life are marked by the accumulation of customs to form material civilization: The earliest weapons were hands and teeth. Next came stones and branches wrenched from trees, fire and flame as soon as these were discovered. Men learnt to use tough iron and copper. With copper they tilled the soil. With copper they whipped up the clashing waves of war... By slow degrees the iron sword came to the fore. Lucretius envisioned a pre-technological human, "far tougher than the men of today... They lived out their lives in the fashion of wild beasts roaming at large." The next stage was the use of huts, clothing and the family. City-states and citadels followed them. Lucretius supposes that the initial
Hand axe
A hand axe is a prehistoric stone tool with two faces, the longest-used tool in human history. It is made from flint or chert, it is characteristic of middle Palaeolithic periods. Its technical name comes from the fact that the archetypical model is bifacial Lithic flake and almond-shaped. Hand axes tend to be symmetrical along their longitudinal axis and formed by percussion; the most common hand axes have a pointed end and rounded base, which gives them their characteristic shape, both faces have been knapped to remove the natural cortex, at least partially. Hand axes are a type of the somewhat wider biface group of two-faced weapons. Hand axes were the first prehistoric tools to be recognized as such: the first published representation of a hand axe was drawn by John Frere and appeared in a British publication in 1800; until that time, their origins were thought to be supernatural. They were called thunderstones, because popular tradition held that they had fallen from the sky during storms or were formed inside the earth by a lightning strike and appeared at the surface.
They are used in some rural areas as an amulet to protect against storms. Hand axe tools were used to butcher animals. Four classes of hand axe are: 1: Large, thick hand axes reduced from cores or thick flakes, referred to as blanks 2: Thinned blanks. While form remains rough and uncertain, an effort has been made to reduce the thickness of the flake or core 3: Either a preform or crude formalized tool, such as an adze 4: Finer formalized tool types such as projectile points and fine bifacesWhile Class 4 hand axes are referred to as "formalized tools", bifaces from any stage of a lithic reduction sequence may be used as tools.. French antiquarian André Vayson de Pradenne introduced the word biface in 1920; this term co-exists with the more popular hand axe, coined by Louis Laurent Gabriel de Mortillet much earlier, The continued use of the word biface by François Bordes and Lionel Balout supported its use in France and Spain, where it replaced the term hand axe. Use of the expression hand axe has continued in English as the equivalent of the French biface, while biface applies more for any piece, carved on both sides by the removal of shallow or deep flakes.
The expression faustkeil is used in German. It can be translated as hand axe, although in a stricter sense it means "fist wedge", it is the same in Dutch where the expression used is vuistbijl which means "fist axe". The same locution occurs in other languages. However, the general impression of these tools were based on ideal pieces that were of such perfect shape that they caught the attention of non-experts, their typology broadened the term's meaning. Biface hand axe and bifacial lithic items are distinguished. A hand axe need not be a bifacial item and many bifacial items are not hand axes. Nor were hand axes and bifacial items exclusive to the Lower Palaeolithic period in the Old World, they appear throughout the world and in many different pre-historical epochs, without implying an ancient origin. Lithic typology was abandoned as a dating system. Examples of this include the "quasi-bifaces" that sometimes appear in strata from the Gravettian and Magdalenian periods in France and Spain, the crude bifacial pieces of the Lupemban culture or the pyriform tools found near Sagua La Grande in Cuba.
The word biface refers to something different in English than biface in French or bifaz in Spanish, which could lead to many misunderstandings. Bifacially carved cutting tools, similar to hand axes, were used to clear scrub vegetation throughout the Neolithic and Chalcolithic periods; these tools were a cheaper alternative to polished axes. The modern day villages along the Sepik river in New Guinea continue to use tools that are identical to hand axes to clear forest. "The term biface should be reserved for items from before the Würm II-III interstadial", although certain objects could exceptionally be called bifaces. Hand axe does not relate to axe, overused in lithic typology to describe a wide variety of stone tools. At the time the use of such items was not understood. In the particular case of Palaeolithic hand axes the term axe is an inadequate description. Lionel Balout stated, "the term should be rejected as an erroneous interpretation of these objects that are not'axes'". Subsequent studies supported this idea those examining the signs of use.
Hand axes are made of flint, but rhyolites, phonolites and other coarse rocks were used as well. Obsidian, natural volcanic glass and was used. Most hand axes have a sharp border all around, No academic consensus describes their use; the pioneers of Palaeolithic tool studies first suggested that bifaces were used as axes or at least for use in demanding physical activities. Other uses showed; the different forms and shapes of known specimens led them to be described as the Acheulean "Swiss Army knife". Each type of tool could have been used for multiple tasks. Wells proposed in 1899 that hand axes were used as missile weapons to hunt prey – an interpretation supported by Calvin, who suggested that some of the rounder specimens of Acheulean hand axes were used as hunting projectiles or as "killer frisbees" meant to be thrown at a herd of animals at a w
Prehistory
Human prehistory is the period between the use of the first stone tools c. 3.3 million years ago by hominins and the invention of writing systems. The earliest writing systems appeared c. 5,300 years ago, but it took thousands of years for writing to be adopted, it was not used in some human cultures until the 19th century or until the present. The end of prehistory therefore came at different dates in different places, the term is less used in discussing societies where prehistory ended recently. Sumer in Mesopotamia, the Indus valley civilization, ancient Egypt were the first civilizations to develop their own scripts and to keep historical records. Neighboring civilizations were the first to follow. Most other civilizations reached the end of prehistory during the Iron Age; the three-age system of division of prehistory into the Stone Age, followed by the Bronze Age and Iron Age, remains in use for much of Eurasia and North Africa, but is not used in those parts of the world where the working of hard metals arrived abruptly with contact with Eurasian cultures, such as the Americas, Oceania and much of Sub-Saharan Africa.
These areas with some exceptions in Pre-Columbian civilizations in the Americas, did not develop complex writing systems before the arrival of Eurasians, their prehistory reaches into recent periods. The period when a culture is written about by others, but has not developed its own writing is known as the protohistory of the culture. By definition, there are no written records from human prehistory, so dating of prehistoric materials is crucial. Clear techniques for dating were not well-developed until the 19th century; this article is concerned with human prehistory, the time since behaviorally and anatomically modern humans first appeared until the beginning of recorded history. Earlier periods are called "prehistoric". Beginning The term "prehistory" can refer to the vast span of time since the beginning of the Universe or the Earth, but more it refers to the period since life appeared on Earth, or more to the time since human-like beings appeared. End The date marking the end of prehistory is defined as the advent of the contemporary written historical record.
The date varies from region to region depending on the date when relevant records become a useful academic resource. For example, in Egypt it is accepted that prehistory ended around 3200 BCE, whereas in New Guinea the end of the prehistoric era is set much more at around 1900 common era. In Europe the well-documented classical cultures of Ancient Greece and Ancient Rome had neighbouring cultures, including the Celts and to a lesser extent the Etruscans, with little or no writing, historians must decide how much weight to give to the highly prejudiced accounts of these "prehistoric" cultures in Greek and Roman literature. Time periods In dividing up human prehistory in Eurasia, historians use the three-age system, whereas scholars of pre-human time periods use the well-defined geologic record and its internationally defined stratum base within the geologic time scale; the three-age system is the periodization of human prehistory into three consecutive time periods, named for their respective predominant tool-making technologies: Stone Age Bronze Age Iron Age The notion of "prehistory" began to surface during the Enlightenment in the work of antiquarians who used the word'primitive' to describe societies that existed before written records.
The first use of the word prehistory in English, occurred in the Foreign Quarterly Review in 1836. The use of the geologic time scale for pre-human time periods, of the three-age system for human prehistory, is a system that emerged during the late nineteenth century in the work of British and Scandinavian archeologists and anthropologists; the main source for prehistory is archaeology, but some scholars are beginning to make more use of evidence from the natural and social sciences. This view has been articulated by advocates of deep history; the primary researchers into human prehistory are archaeologists and physical anthropologists who use excavation and geographic surveys, other scientific analysis to reveal and interpret the nature and behavior of pre-literate and non-literate peoples. Human population geneticists and historical linguists are providing valuable insight for these questions. Cultural anthropologists help provide context for societal interactions, by which objects of human origin pass among people, allowing an analysis of any article that arises in a human prehistoric context.
Therefore, data about prehistory is provided by a wide variety of natural and social sciences, such as paleontology, archaeology, geology, comparative linguistics, molecular genetics and many others. Human prehistory differs from history not only in terms of its chronology but in the way it deals with the activities of archaeological cultures rather than named nations or individuals. Restricted to material processes and artifacts rather than written records, prehistory is anonymous; because of this, reference terms that prehistorians use, such as Neanderthal or Iron Age are modern labels with definitions sometimes subject to debate. The concept of a "Stone Age" is found useful in the archaeology of most of the world, though in the archaeology of the Americas it is called by different names and begins with a Lithic sta
Hazelnut
The hazelnut is the nut of the hazel and therefore includes any of the nuts deriving from species of the genus Corylus the nuts of the species Corylus avellana. It is known as cobnut or filbert nut according to species. A cob is spherical to oval, about 15–25 mm long and 10–15 mm in diameter, with an outer fibrous husk surrounding a smooth shell. A filbert is more elongated, being about twice as long as its diameter; the nut falls out of the husk when ripe, about 7 to 8 months after pollination. The kernel of the seed is edible and ground into a paste; the seed has a dark brown skin, which sometimes is removed before cooking. Hazelnuts are used in confectionery to make praline, used in combination with chocolate for chocolate truffles and products such as Nutella and Frangelico liqueur. Hazelnut oil, pressed from hazelnuts, is flavoured and used as a cooking oil. Turkey is the world's largest producer of hazelnuts. Hazelnuts are rich in protein, monounsaturated fat, vitamin E, numerous other essential nutrients.
In 1995, evidence of large-scale Mesolithic nut processing, some 8,000 years old, was found in a midden pit on the island of Colonsay in Scotland. The evidence consists of a large, shallow pit full of the remains of hundreds of thousands of burned hazelnut shells. Hazelnuts have been found on other Mesolithic sites, but in such quantities or concentrated in one pit; the nuts were radiocarbon dated to 7720+/-110BP, which calibrates to circa 6000 BC. Similar sites in Britain are known only at Cass ny Hawin on the Isle of Man; this discovery gives an insight into communal planning in the period. The nuts were harvested in a single year, pollen analysis suggests the hazel trees were all cut down at the same time; the scale of the activity and the lack of large game on the island, suggest the possibility that Colonsay contained a community with a vegetarian diet for the time they spent on the island. The pit was on a beach close to the shore, was associated with two smaller, stone-lined pits whose function remains obscure, a hearth, a second cluster of pits.
The traditional method to increase nut production is called'brutting', which involves prompting more of the trees' energy to go into flower bud production, by snapping, but not breaking off, the tips of the new year shoots' six or seven leaf groups from where they join with the trunk or branch, at the end of the growing season. The traditional term for an area of cultivated hazelnuts is a plat. Ferrero SpA, the maker of Nutella and Ferrero Rocher, uses 25% of the global supply of hazelnuts. Hazelnuts are used in confections to make pralines, chocolate truffles, hazelnut paste products. In Austria, hazelnut paste is an ingredient such as Viennese hazelnut torte. In Kiev cake, hazelnut flour is used to flavor its meringue body, crushed hazelnuts are sprinkled over its sides. Dacquoise, a French dessert cake contains a layer of hazelnut meringue. Hazelnuts are used in Georgian cuisine. Hazelnuts are a common constituent of muesli; the nuts may be eaten having different flavors. The many cultivars of the hazel include'Atababa','Barcelona','Butler','Casina','Clark','Cosford','Daviana','Delle Langhe','England','Ennis','Fillbert','Halls Giant','Jemtegaard','Kent Cob','Lewis','Tokolyi','Tonda Gentile','Tonda di Giffoni','Tonda Romana','Wanliss Pride', and'Willamette'.
Some of these are grown for specific qualities of the nut, including large nut size, or early or late fruiting, whereas others are grown as pollinators. The majority of commercial hazelnuts are propagated from root sprouts; some cultivars are of hybrid origin between common filbert. Hazelnuts are harvested annually in mid-autumn; as autumn comes to a close, the trees leaves. Most commercial growers wait for the nuts to drop on their own, rather than using equipment to shake them from the tree; the harvesting of hazelnuts is performed either by hand or, by manual or mechanical raking of fallen nuts. Four primary pieces of equipment are used in commercial harvesting: the sweeper, the harvester, the nut cart, the forklift; the sweeper moves the nuts into the center of the rows, the harvester lifts and separates the nuts from any debris, the nut cart holds the nuts picked up by the harvester, the forklift brings a tote to offload the nuts from the nut cart and stacks the totes to be shipped to the processor.
The sweeper is a low-to-the-ground machine. It has a 2 m belt attached to the front that rotates to sweep leaves and small twigs from left to right, depositing the material in the center of the row as it drives forward. On the rear of the sweeper is a powerful blower to blow material left into the adjacent row with air speeds up to 90 m/s. Careful grooming during the year and patient blowing at harvest may eliminate the need for hand raking around the trunk of the tree, where nuts may accumulate; the sweeper prepares a single center row of nuts narrow enough for the harvesting tractor to drive over without driving on the center row. It is best to sweep only a few rows ahead of the harvesters at any given time, to prevent the tractor that drives the harvester from crushing the nuts that may still be falling from the trees. Hazelnut orchards may be harvested up to three times during the harvest season, depending on the quantity of nuts in the trees and the rate of nut drop as a result of weather.
The harvester is a slow-moving machine pushed by a tractor, w
