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76-643: The Butmir region is very rich in flint . A small stream passes through before connecting to the Željeznica river in central Ilidža. Butmir is known for archaeological finds dating back to the Neolithic period. The residents some 5,000 years ago formed a distinct group, which is today known as the Butmir Culture . Football Club Plavi Put is located in Butmir. Butmir contains an important NATO base in this region. The Butmir Training Centre near Sarajevo

152-432: A black residue which is known as "amber colophony", or "amber pitch"; when dissolved in oil of turpentine or in linseed oil this forms "amber varnish" or "amber lac". Molecular polymerization, resulting from high pressures and temperatures produced by overlying sediment, transforms the resin first into copal . Sustained heat and pressure drives off terpenes and results in the formation of amber. For this to happen,

228-415: A communic acid base, and they also include much succinic acid. Baltic amber yields on dry distillation succinic acid, the proportion varying from about 3% to 8%, and being greatest in the pale opaque or bony varieties. The aromatic and irritating fumes emitted by burning amber are mainly from this acid. Baltic amber is distinguished by its yield of succinic acid , hence the name succinite . Succinite has

304-466: A fire with the correct tinder , or gunpowder used in weapons , namely the flintlock firing mechanism . Although it has been superseded in these uses by different processes (the percussion cap ), or materials ( ferrocerium ), "flint" has lent its name as generic term for a fire starter. The exact mode of formation of flint is not yet clear, but it is thought that it occurs as a result of chemical changes in compressed sedimentary rock formations during

380-514: A hardness between 2 and 3, which is greater than many other fossil resins. Its specific gravity varies from 1.05 to 1.10. It can be distinguished from other ambers via infrared spectroscopy through a specific carbonyl absorption peak. Infrared spectroscopy can detect the relative age of an amber sample. Succinic acid may not be an original component of amber but rather a degradation product of abietic acid . Class Ib ambers are based on communic acid; however, they lack succinic acid. Class Ic

456-461: A high level of wastage, flint finishes typically indicate high status buildings. During World War I, in the chalky-soil country of France, the British filled sandbags with flint and used these sandbags as breastworks. 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 based on colour; those having

532-682: A large island—three days' sail from the Scythian coast and called Balcia by Xenophon of Lampsacus (author of a fanciful travel book in Greek)—as Basilia —a name generally equated with Abalus . Given the presence of amber, the island could have been Heligoland , Zealand , the shores of Gdańsk Bay , the Sambia Peninsula or the Curonian Lagoon , which were historically the richest sources of amber in northern Europe. It

608-558: A large scale in the formation of "ambroid" or "pressed amber". The pieces are carefully heated with exclusion of air and then compressed into a uniform mass by intense hydraulic pressure, the softened amber being forced through holes in a metal plate. The product is extensively used for the production of cheap jewelry and articles for smoking. This pressed amber yields brilliant interference colors in polarized light." Amber has often been imitated by other resins like copal and kauri gum , as well as by celluloid and even glass. Baltic amber

684-497: A later 2013 study was unable to extract DNA from insects trapped in much more recent Holocene copal . In 1938, 12-year-old David Attenborough (brother of Richard who played John Hammond in Jurassic Park ) was given a piece of amber containing prehistoric creatures from his adoptive sister; it would be the focus of his 2004 BBC documentary The Amber Time Machine . Amber has been used since prehistory ( Solutrean ) in

760-417: A single species; and indeed a large number of conifers belonging to different genera are represented in the amber-flora. Amber is a unique preservational mode, preserving otherwise unfossilizable parts of organisms; as such it is helpful in the reconstruction of ecosystems as well as organisms; the chemical composition of the resin, however, is of limited utility in reconstructing the phylogenetic affinity of

836-447: A temperature of 150 to 260 °C (300 to 500 °F) for 24 hours, then slowly cooled to room temperature. This makes the material more homogeneous and thus more knappable and produces tools with a cleaner, sharper cutting edge. Heat treating was known to Stone Age artisans. When struck against steel, a flint edge produces sparks. The hard flint edge shaves off a particle of the steel that exposes iron, which reacts with oxygen from

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912-577: A term ἠλέκτωρ ( ēlektōr ) meaning "beaming Sun". According to myth, when Phaëton son of Helios (the Sun) was killed, his mourning sisters became poplar trees, and their tears became elektron , amber. The word elektron gave rise to the words electric, electricity , and their relatives because of amber's ability to bear a charge of static electricity . Pliny the Elder says that the German name of amber

988-429: A third type of resin, which is often found as amber within their veins. The composition of resins is highly variable; each species produces a unique blend of chemicals which can be identified by the use of pyrolysis – gas chromatography – mass spectrometry . The overall chemical and structural composition is used to divide ambers into five classes. There is also a separate classification of amber gemstones, according to

1064-474: A tint of red, indicating high iron content, are discarded. The remaining blue-grey stones have a low content of chromophoric oxides and so are less deleterious to the colour of the ceramic composition after firing. Until recently calcined flint was also an important raw material in clay-based ceramic bodies produced in the UK. In clay bodies , calcined flint attenuates the shrinkage whilst drying, and modifies

1140-548: A tree of the pine genus, is the fact that it emits a pine-like smell when rubbed, and that it burns, when ignited, with the odour and appearance of torch-pine wood. He also states that amber is also found in Egypt and India, and he even refers to the electrostatic properties of amber, by saying that "in Syria the women make the whorls of their spindles of this substance, and give it the name of harpax [from ἁρπάζω, "to drag"] from

1216-546: A variety of cutting tools, such as knife blades and scrapers. The use of flint to make stone tools dates back more than three million years; flint's extreme durability has made it possible to accurately date its use over this time. Flint is one of the primary materials used to define the Stone Age . During the Stone Age, access to flint was so important for survival that people would travel or trade long distances to obtain

1292-442: A very strong reflection, almost white. Only about 100 kg (220 lb) is found per year, which makes it valuable and expensive. Sometimes amber retains the form of drops and stalactites , just as it exuded from the ducts and receptacles of the injured trees. It is thought that, in addition to exuding onto the surface of the tree, amber resin also originally flowed into hollow cavities or cracks within trees, thereby leading to

1368-418: A wider range of tinders. Because it can produce sparks when wet and can start fires when used correctly, ferrocerium is commonly included in survival kits . Ferrocerium is used in many cigarette lighters, where it is referred to as "a flint". Flint's utility as a fire starter is hampered by its property of uneven expansion under heating, causing it to fracture, sometimes violently, during heating. This tendency

1444-507: Is Highgate copalite . The oldest amber recovered dates to the late Carboniferous period ( 320  million years ago ). Its chemical composition makes it difficult to match the amber to its producers – it is most similar to the resins produced by flowering plants; however, the first flowering plants appeared in the Early Cretaceous, about 200 million years after the oldest amber known to date, and they were not common until

1520-483: Is fossilized tree resin . Examples of it have been appreciated for its color and natural beauty since the Neolithic times, and worked as a gemstone since antiquity. Amber is used in jewelry and as a healing agent in folk medicine . There are five classes of amber, defined on the basis of their chemical constituents. Because it originates as a soft, sticky tree resin, amber sometimes contains animal and plant material as inclusions . Amber occurring in coal seams

1596-441: Is heterogeneous in composition, but consists of several resinous bodies more or less soluble in alcohol , ether and chloroform , associated with an insoluble bituminous substance. Amber is a macromolecule formed by free radical polymerization of several precursors in the labdane family, for example, communic acid , communol , and biformene . These labdanes are diterpenes (C 20 H 32 ) and trienes, equipping

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1672-473: Is also called resinite , and the term ambrite is applied to that found specifically within New Zealand coal seams. The English word amber derives from Arabic ʿanbar عنبر (ultimately from Middle Persian ambar ) via Middle Latin ambar and Middle French ambre . The word referred to what is now known as ambergris ( ambre gris or "gray amber"), a solid waxy substance derived from

1748-411: Is as yet impossible, since no amber with fossilized mosquitoes has ever yielded preserved blood. Amber is, however, conducive to preserving DNA , since it dehydrates and thus stabilizes organisms trapped inside. One projection in 1999 estimated that DNA trapped in amber could last up to 100 million years, far beyond most estimates of around 1 million years in the most ideal conditions, although

1824-747: Is assumed that there were well-established trade routes for amber connecting the Baltic with the Mediterranean (known as the " Amber Road "). Pliny states explicitly that the Germans exported amber to Pannonia , from where the Veneti distributed it onwards. The ancient Italic peoples of southern Italy used to work amber; the National Archaeological Museum of Siritide (Museo Archeologico Nazionale della Siritide) at Policoro in

1900-527: Is enhanced by the impurities found in most samples of flint that may expand to a greater or lesser degree than the surrounding stone, and is similar to the tendency of glass to shatter when exposed to heat, and can become a drawback when flint is used as a building material . Flint, knapped or unknapped, has been used from antiquity (for example at the Late Roman fort of Burgh Castle in Norfolk) up to

1976-601: Is even an ammonite Puzosia (Bhimaites) and marine gastropods found in Burmese amber . The preservation of prehistoric organisms in amber forms a key plot point in Michael Crichton 's 1990 novel Jurassic Park and the 1993 movie adaptation by Steven Spielberg . In the story, scientists are able to extract the preserved blood of dinosaurs from prehistoric mosquitoes trapped in amber, from which they genetically clone living dinosaurs. Scientifically this

2052-431: Is given by polishing with flannel. When gradually heated in an oil bath, amber "becomes soft and flexible. Two pieces of amber may be united by smearing the surfaces with linseed oil, heating them, and then pressing them together while hot. Cloudy amber may be clarified in an oil bath, as the oil fills the numerous pores that cause the turbidity. Small fragments, formerly thrown away or used only for varnish are now used on

2128-523: Is globally distributed in or around all continents , mainly in rocks of Cretaceous age or younger. Historically, the coast west of Königsberg in Prussia was the world's leading source of amber. The first mentions of amber deposits there date back to the 12th century. Juodkrantė in Lithuania was established in the mid-19th century as a mining town of amber. About 90% of the world's extractable amber

2204-446: Is mainly based on enantio -labdatrienonic acids, such as ozic and zanzibaric acids. Its most familiar representative is Dominican amber,. which is mostly transparent and often contains a higher number of fossil inclusions. This has enabled the detailed reconstruction of the ecosystem of a long-vanished tropical forest. Resin from the extinct species Hymenaea protera is the source of Dominican amber and probably of most amber found in

2280-504: Is mined through bell pitting , which is dangerous because of the risk of tunnel collapse. An important source of amber is Kachin State in northern Myanmar , which has been a major source of amber in China for at least 1,800 years. Contemporary mining of this deposit has attracted attention for unsafe working conditions and its role in funding internal conflict in the country . Amber from

2356-523: Is one of the 15 verified NATO training centres. The Butmir Training Centre was formed in April 2005 through partnership of 12 countries, including the United States . [1] Flint Flint , occasionally flintstone , is a sedimentary cryptocrystalline form of the mineral quartz , categorized as the variety of chert that occurs in chalk or marly limestone . Historically, flint

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2432-405: Is produced from a marrow discharged by trees belonging to the pine genus, like gum from the cherry, and resin from the ordinary pine. It is a liquid at first, which issues forth in considerable quantities, and is gradually hardened [...] Our forefathers, too, were of opinion that it is the juice of a tree, and for this reason gave it the name of "succinum" and one great proof that it is the produce of

2508-621: Is rare and highly sought after. Yellow amber is a hard fossil resin from evergreen trees, and despite the name it can be translucent, yellow, orange, or brown colored. Known to the Iranians by the Pahlavi compound word kah-ruba (from kah "straw" plus rubay "attract, snatch", referring to its electrical properties ), which entered Arabic as kahraba' or kahraba (which later became the Arabic word for electricity , كهرباء kahrabā ' ), it too

2584-794: Is referred to as knapping . Flint mining is attested since the Paleolithic , but became more common since the Neolithic (Michelsberg culture, Funnelbeaker culture ). 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 , Thy in Jutland (flint mine at Hov), the Sennonian deposits of Rügen , Grimes Graves in England,

2660-625: Is roughly 125–135 million years old, is considered of high scientific value, providing evidence of some of the oldest sampled ecosystems. In Lebanon, more than 450 outcrops of Lower Cretaceous amber were discovered by Dany Azar, a Lebanese paleontologist and entomologist. Among these outcrops, 20 have yielded biological inclusions comprising the oldest representatives of several recent families of terrestrial arthropods. Even older Jurassic amber has been found recently in Lebanon as well. Many remarkable insects and spiders were recently discovered in

2736-407: Is sometimes colored artificially but also called "true amber". Amber occurs in a range of different colors. As well as the usual yellow-orange-brown that is associated with the color "amber", amber can range from a whitish color through a pale lemon yellow, to brown and almost black. Other uncommon colors include red amber (sometimes known as "cherry amber"), green amber, and even blue amber , which

2812-790: Is still located in that area, which was transferred to the Russian Soviet Federative Socialist Republic of the USSR in 1946, becoming the Kaliningrad Oblast . Pieces of amber torn from the seafloor are cast up by the waves and collected by hand, dredging, or diving. Elsewhere, amber is mined, both in open works and underground galleries. Then nodules of blue earth have to be removed and an opaque crust must be cleaned off, which can be done in revolving barrels containing sand and water. Erosion removes this crust from sea-worn amber. Dominican amber

2888-866: The Late Cretaceous . Amber becomes abundant long after the Carboniferous, in the Early Cretaceous , when it is found in association with insects. The oldest amber with arthropod inclusions comes from the Late Triassic (late Carnian c. 230 Ma) of Italy, where four microscopic (0.2–0.1 mm) mites, Triasacarus , Ampezzoa , Minyacarus and Cheirolepidoptus , and a poorly preserved nematoceran fly were found in millimetre-sized droplets of amber. The oldest amber with significant numbers of arthropod inclusions comes from Lebanon. This amber, referred to as Lebanese amber ,

2964-508: The Rivne Oblast of Ukraine, referred to as Rivne amber , is mined illegally by organised crime groups, who deforest the surrounding areas and pump water into the sediments to extract the amber, causing severe environmental deterioration. The Vienna amber factories, which use pale amber to manufacture pipes and other smoking tools, turn it on a lathe and polish it with whitening and water or with rotten stone and oil. The final luster

3040-496: The percussion cap from the 1840s onward, flintlock rifles and shotguns remain in use amongst recreational shooters. Flint and steel used to strike sparks were superseded in the 20th century by ferrocerium (sometimes referred to as "flint", although not true flint, " mischmetal ", "hot spark", "metal match", or "fire steel"). This human-made material, when scraped with any hard, sharp edge, produces sparks that are much hotter than obtained with natural flint and steel, allowing use of

3116-452: The province of Matera ( Basilicata ) displays important surviving examples. It has been suggested that amber used in antiquity, as at Mycenae and in the prehistory of the Mediterranean, came from deposits in Sicily . Pliny also cites the opinion of Nicias ( c. 470–413 BCE), according to whom amber is a liquid produced by the rays of the sun; and that these rays, at the moment of

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3192-583: The sperm whale . The word, in its sense of "ambergris," was adopted in Middle English in the 14th century. In the Romance languages , the sense of the word was extended to Baltic amber (fossil resin) from as early as the late 13th century. At first called white or yellow amber ( ambre jaune ), this meaning was adopted in English by the early 15th century. As the use of ambergris waned, this became

3268-616: The 18th century, thus modern German Bernstein besides Dutch barnsteen . In the Baltic languages , the Lithuanian term for amber is gintaras and the Latvian dzintars . These words, and the Slavic jantar and Hungarian gyanta ('resin'), are thought to originate from Phoenician jainitar ("sea-resin"). A number of regional and varietal names have been applied to ambers over

3344-562: The Baltic ambers and another that resembles the Agathis group. Fossil resins from the Americas and Africa are closely related to the modern genus Hymenaea , while Baltic ambers are thought to be fossil resins from plants of the family Sciadopityaceae that once lived in north Europe. The abnormal development of resin in living trees ( succinosis ) can result in the formation of amber. Impurities are quite often present, especially when

3420-592: The Ocean called Mentonomon, their territory extending a distance of six thousand stadia; that, at one day's sail from this territory, is the Isle of Abalus , upon the shores of which, amber is thrown up by the waves in spring, it being an excretion of the sea in a concrete form; as, also, that the inhabitants use this amber by way of fuel, and sell it to their neighbors, the Teutones . Earlier Pliny says that Pytheas refers to

3496-976: The Upper Cretaceous chalk formation of Dobruja and the lower Danube (Balkan flint), the Cenomanian chalky marl formation of the Moldavian Plateau (Miorcani flint) and the Jurassic deposits of the Kraków area and Krzemionki in Poland, as well as of the Lägern ( silex ) in the Jura Mountains of Switzerland. In 1938, a project of the Ohio Historical Society , under the leadership of H. Holmes Ellis began to study

3572-503: The amber of Jordan including the oldest zorapterans , clerid beetles , umenocoleid roaches , and achiliid planthoppers . Burmese amber from the Hukawng Valley in northern Myanmar is the only commercially exploited Cretaceous amber. Uranium–lead dating of zircon crystals associated with the deposit have given an estimated depositional age of approximately 99 million years ago. Over 1,300 species have been described from

3648-410: The amber while the resin was yet fresh, suggesting relations with the flora of eastern Asia and the southern part of North America. Heinrich Göppert named the common amber-yielding pine of the Baltic forests Pinites succiniter , but as the wood does not seem to differ from that of the existing genus it has been also called Pinus succinifera . It is improbable that the production of amber was limited to

3724-531: The amber, with over 300 in 2019 alone. Baltic amber is found as irregular nodules in marine glauconitic sand, known as blue earth , occurring in Upper Eocene strata of Sambia in Prussia. It appears to have been partly derived from older Eocene deposits and it occurs also as a derivative phase in later formations, such as glacial drift . Relics of an abundant flora occur as inclusions trapped within

3800-510: The atmosphere and can ignite the proper tinder . Prior to the wide availability of steel, rocks of pyrite (FeS 2 ) would be used along with the flint, in a similar (but more time-consuming) way. These methods remain popular in woodcraft, bushcraft, and amongst people practising traditional fire-starting skills. A later, major use of flint and steel was in the flintlock mechanism , used primarily in flintlock firearms, but also used on dedicated fire-starting tools. A piece of flint held in

3876-404: The beaches at Beeston Bump and West Runton . The "Ohio flint" is the official gemstone of Ohio state. It is formed from limey debris that was deposited at the bottom of inland Paleozoic seas hundreds of millions of years ago that hardened into limestone and later became infused with silica . The flint from Flint Ridge is found in many hues like red, green, pink, blue, white, and grey, with

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3952-459: The centuries, including Allingite , Beckerite , Gedanite , Kochenite , Krantzite , and Stantienite . Theophrastus discussed amber in the 4th century BCE, as did Pytheas ( c.  330 BCE ), whose work "On the Ocean" is lost, but was referenced by Pliny, according to whose Natural History : Pytheas says that the Gutones , a people of Germany, inhabit the shores of an estuary of

4028-619: The circumstance that it attracts leaves towards it, chaff, and the light fringe of tissues". The Romans traded for amber from the shores of the southern Baltic at least as far back as the time of Nero . Amber has a long history of use in China, with the first written record from 200 BCE. Early in the 19th century, the first reports of amber found in North America came from discoveries in New Jersey along Crosswicks Creek near Trenton , at Camden , and near Woodbury . Amber

4104-429: The colour variations caused by minute impurities of iron compounds. Flint can be coloured: sandy brown, medium to dark grey, black, reddish brown or an off-white grey. Flint was used in the manufacture of tools during the Stone Age as it splits into thin, sharp splinters called flakes or blades (depending on the shape) when struck by another hard object (such as a hammerstone made of another material). This process

4180-452: The development of large lumps of amber of irregular form. Amber can be classified into several forms. Most fundamentally, there are two types of plant resin with the potential for fossilization. Terpenoids , produced by conifers and angiosperms , consist of ring structures formed of isoprene (C 5 H 8 ) units. Phenolic resins are today only produced by angiosperms, and tend to serve functional uses. The extinct medullosans produced

4256-425: The fired thermal expansion. Flint can also be used in glazes as a network former. In preparation for use flint pebbles, frequently sourced from the coasts of South-East England or Western France, were calcined to around 1,000 °C (1,800 °F). This heating process both removed organic impurities and induced certain physical reactions, including converting some of the quartz to cristobalite . After calcination

4332-535: The flint pebbles were crushed and milled to a fine particle size. However, the use of flint has now been superseded by quartz . Because of the historical use of flint, the word "flint" is used by some potters (especially in the U.S.) to refer generically to siliceous raw materials used in ceramics that are not flint. Flint bracelets were known in Ancient Egypt, and several examples have been found. Mineralogy Archaeology Amber Amber

4408-408: The jaws of a spring-loaded hammer, when released by a trigger, strikes a hinged piece of steel (" frizzen ") at an angle, creating a shower of sparks and exposing a charge of priming powder. The sparks ignite the priming powder and that flame, in turn, ignites the main charge, propelling the ball, bullet, or shot through the barrel. While the military use of the flintlock declined after the adoption of

4484-543: The knapping methods and techniques of Native Americans . Like past studies, this work involved experimenting with actual knapping techniques by creation of stone tools through the use of techniques like direct freehand percussion, freehand pressure and pressure using a rest. Other scholars who have conducted similar experiments and studies include William Henry Holmes , Alonzo W. Pond , Francis H. S. Knowles and Don Crabtree . To reduce susceptibility to fragmentation, flint/chert may be heat-treated, being slowly brought up to

4560-409: The main sense of the word. The two substances ("yellow amber" and "gray amber") conceivably became associated or confused because they both were found washed up on beaches. Ambergris is less dense than water and floats, whereas amber is too dense to float, though less dense than stone. The classical names for amber, Latin electrum and Ancient Greek ἤλεκτρον ( ēlektron ), are connected to

4636-413: The most highly prized amber is transparent, in contrast to the very common cloudy amber and opaque amber. Opaque amber contains numerous minute bubbles. This kind of amber is known as "bony amber". Although all Dominican amber is fluorescent, the rarest Dominican amber is blue amber. It turns blue in natural sunlight and any other partially or wholly ultraviolet light source. In long-wave UV light it has

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4712-543: The organic skeleton with three alkene groups for polymerization . As amber matures over the years, more polymerization takes place as well as isomerization reactions, crosslinking and cyclization . Most amber has a hardness between 2.0 and 2.5 on the Mohs scale , a refractive index of 1.5–1.6, a specific gravity between 1.06 and 1.10, and a melting point of 250–300 °C. Heated above 200 °C (392 °F), amber decomposes, yielding an oil of amber , and leaves

4788-475: The present day as a material for building stone walls, using lime mortar, and often combined with other available stone or brick rubble. It was most common in those parts of southern England where no good building stone was available locally, and where brick-making was not widespread until the later Middle Ages. It is especially associated with East Anglia , but also used in chalky areas stretching through Hampshire , Sussex, Surrey and Kent to Somerset . Flint

4864-442: The process of diagenesis . One hypothesis is that a gelatinous material fills cavities in the sediment, such as holes bored by crustaceans or molluscs and that this becomes silicified . This hypothesis would certainly explain the complex shapes of flint nodules that are found. The source of dissolved silica in the porous media could be the spicules of silicious sponges ( demosponges ). Certain types of flint, such as that from

4940-533: The resin has dropped onto the ground, so the material may be useless except for varnish-making. Such impure amber is called firniss . Such inclusion of other substances can cause the amber to have an unexpected color. Pyrites may give a bluish color. Bony amber owes its cloudy opacity to numerous tiny bubbles inside the resin. However, so-called black amber is really a kind of jet . In darkly clouded and even opaque amber, inclusions can be imaged using high-energy, high-contrast, high-resolution X-rays . Amber

5016-454: The resin must be resistant to decay. Many trees produce resin, but in the majority of cases this deposit is broken down by physical and biological processes. Exposure to sunlight, rain, microorganisms, and extreme temperatures tends to disintegrate the resin. For the resin to survive long enough to become amber, it must be resistant to such forces or be produced under conditions that exclude them. Fossil resins from Europe fall into two categories,

5092-470: The resin producer. Amber sometimes contains animals or plant matter that became caught in the resin as it was secreted. Insects , spiders and even their webs, annelids , frogs , crustaceans , bacteria and amoebae , marine microfossils, wood, flowers and fruit, hair, feathers and other small organisms have been recovered in Cretaceous ambers (deposited c. 130  million years ago ). There

5168-759: The south coast of England and its counterpart on the French side of the Channel , contain trapped fossilised marine flora. Pieces of coral and vegetation have been found preserved inside the flint similar to insects and plant parts within amber . Thin slices of the stone often reveal this effect. Flint sometimes occurs in large flint fields in Jurassic or Cretaceous beds, for example, in Europe. Puzzling giant flint formations known as paramoudra and flint circles are found around Europe but especially in Norfolk, England, on

5244-627: The stone. Grime's Graves was an important source of flint traded across Europe. Flint Ridge in Ohio was another important source of flint, and Native Americans extracted the flint from hundreds of quarries along the ridge. This "Ohio Flint" was traded across the eastern United States, and has been found as far west as the Rocky Mountains and south around the Gulf of Mexico . When struck against steel, flint will produce enough sparks to ignite

5320-557: The sun's setting, striking with the greatest force upon the surface of the soil, leave upon it an unctuous sweat, which is carried off by the tides of the Ocean, and thrown up upon the shores of Germany. Besides the fanciful explanations according to which amber is "produced by the Sun", Pliny cites opinions that are well aware of its origin in tree resin, citing the native Latin name of succinum ( sūcinum , from sucus "juice"). In Book 37, section XI of Natural History , Pliny wrote: Amber

5396-473: The tropics. It is not "succinite" but " retinite ". These ambers are formed from resins with a sesquiterpenoid base, such as cadinene . These ambers are polystyrenes . Class IV is something of a catch-all : its ambers are not polymerized, but mainly consist of cedrene -based sesquiterpenoids. Class V resins are considered to be produced by a pine or pine relative. They comprise a mixture of diterpinoid resins and n -alkyl compounds. Their main variety

5472-449: The way of production. This class is by far the most abundant. It comprises labdatriene carboxylic acids such as communic or ozic acids . It is further split into three sub-classes. Classes Ia and Ib utilize regular labdanoid diterpenes (e.g. communic acid, communol, biformenes), while Ic uses enantio labdanoids (ozic acid, ozol, enantio biformenes). Class Ia includes Succinite (= 'normal' Baltic amber) and Glessite . They have

5548-696: Was glæsum , "for which reason the Romans, when Germanicus commanded the fleet in those parts, gave to one of these islands the name of Glæsaria, which by the barbarians was known as Austeravia". This is confirmed by the recorded Old High German word glas and by the Old English word glær for "amber" (compare glass ). In Middle Low German , amber was known as berne-, barn-, börnstēn (with etymological roots related to "burn" and to "stone" ). The Low German term became dominant also in High German by

5624-625: Was called amber in Europe (Old French and Middle English ambre). Found along the southern shore of the Baltic Sea, yellow amber reached the Middle East and western Europe via trade. Its coastal acquisition may have been one reason yellow amber came to be designated by the same term as ambergris. Moreover, like ambergris, the resin could be burned as an incense. The resin's most popular use was, however, for ornamentation—easily cut and polished, it could be transformed into beautiful jewelry. Much of

5700-427: Was used in the construction of many churches, houses, and other buildings, for example, the large stronghold of Framlingham Castle . Many different decorative effects have been achieved by using different types of knapping or arrangement and combinations with stone ( flushwork ), especially in the 15th and early 16th centuries. Because knapping flints to a relatively flush surface and size is a highly skilled process with

5776-557: Was widely used to make stone tools and start fires . Flint occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones . Inside the nodule, flint is usually dark grey or black, green, white, or brown in colour, and has a glassy or waxy appearance. A thin, oxidised layer on the outside of the nodules is usually different in colour, typically white and rough in texture. The nodules can often be found along streams and beaches . Flint breaks and chips into sharp-edged pieces, making it useful in constructing

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