Amber is fossilized tree resin. It has been appreciated for its color (orange, brown and, sometimes, red) and natural beauty since Neolithic times, and worked as a gemstone since classical antiquity."Amber" (2004). In Maxine N. Lurie and Marc Mappen (eds.) Encyclopedia of New Jersey, Rutgers University Press, . Amber is used in jewelry and as a healing agent in folk medicine.
There are over 150 types of Amber and 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 is also called resinite, and the term ambrite is applied to that found specifically within New Zealand coal seams.Poinar GO, Poinar R. (1995) The quest for life in amber. Basic Books, , p. 133
Etymology The English word amber derives from Arabic from Middle Persian ( , "ambergris") via Middle Latin and Middle French . The word referred to what is now known as ambergris (ambre gris or "gray amber"), a solid waxy substance derived from 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 (), this meaning was adopted in English by the early 15th century. As the use of ambergris waned, this became 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 denser and floats only in concentrated saline, or strong salty seawater though less dense than stone.see: Abu Zaid al Hassan from Siraf & Sulaiman the Merchant (851), Silsilat-al-Tawarikh (travels in Asia).
The classical names for amber, Ancient Greek () and one of its Latin names, electrum, are connected to a term () meaning "beaming Sun".Homeric (Iliad 6.513, 19.398). The feminine being later used as a name of the Moon.The derivation of the modern term "electric" from the Greek word for amber dates to the 1600 (Latin electricus "amber-like", in De Magnete by William Gilbert). . The word "electron" (for the fundamental particle) was coined in 1891 by the Irish physicist George Stoney whilst analyzing elementary charges for the first time. . According to myth, when Phaëton, son of Helios (the Sun), was killed his mourning sisters became poplar trees, and their tears became elektron, amber.Michael R. Collings, Gemlore: An Introduction to Precious and Semi-Precious Stones, 2009, p. 20 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."Electric." Online Etymological Dictionary. Retrieved 6 September 2018. This property is due to its effectiveness as an electrical insulator, which does not allow electron motion from the surface through the substance.
Varietal names A number of regional and varietal names have been applied to ambers over the centuries, including allingite, beckerite, gedanite, kochenite, krantzite, and stantienite.
History Theophrastus discussed amber in the 4th century BCE, as did Pytheas (), whose work "On the Ocean" is lost, but was referenced by Pliny, according to whose Natural History:Natural History 37.11 .Pytheas says that the Gutones, a people of Germany, inhabit the shores of an estuary of 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 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.Natural History IV.27.13 or IV.13.95 in the Loeb edition. 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. 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 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 ( 470–413 BCE), according to whom amber 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").Compare succinic acid as well as succinite, a term given to a particular type of amber by James Dwight Dana In Book 37, section XI of Natural History, Pliny wrote:
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 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.
Composition Amber is heterogeneous in composition, consisting of several resinous substances that are more or less soluble in alcohol, ether, and chloroform, along with an insoluble bituminous fraction. It is a macromolecule formed by free radical polymerization of terpenoid precursors—diterpenes in gymnosperms, particularly labdane-type compounds such as communic acid, communol, and biformene.Manuel Villanueva-García, Antonio Martínez-Richa, and Juvencio Robles Assignment of vibrational spectra of labdatriene derivatives and ambers: A combined experimental and density functional theoretical study Arkivoc (EJ-1567C) pp. 449–458 In angiosperms, the terpenoids are dominated by triterpenes, although amber from the family Fabaceae also contains labdane-based diterpenes. These compounds provide alkene groups that enable polymerization. Over time, amber matures through further polymerization, isomerization, crosslinking, and cyclization, resulting in its characteristic stable, fossilized structure.
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 , amber decomposes, yielding an oil of amber, and leaves 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".
Impurities are quite often present, especially when 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.
Formation 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, 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.Poinar, George O. (1992) Life in amber. Stanford, Calif.: Stanford University Press, p. 12, Fossil resins from Europe fall into two categories, 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.
Extraction and processing
Distribution and mining
Amber 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 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 is mined through bell pitting, which is dangerous because of the risk of tunnel collapse.Wichard, Wilfred and Weitschat, Wolfgang (2004) Im Bernsteinwald. – Gerstenberg Verlag, Hildesheim,
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 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.
Treatment 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 is given by polishing with flannel.