1.
Alluvium
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Alluvium is loose, unconsolidated soil or sediments, which has been eroded, reshaped by water in some form, and redeposited in a non-marine setting. Alluvium is typically made up of a variety of materials, including fine particles of silt and clay and larger particles of sand, when this loose alluvial material is deposited or cemented into a lithological unit, or lithified, it is called an alluvial deposit. The term alluvium is not typically used in situations where the formation of the sediment can clearly be attributed to another process that is well described. This includes, lake sediments, river sediments, or glacially-derived sediments, sediments that are formed or deposited in a perennial stream or river are typically not referred to as alluvial. Most alluvium is very young, and is often referred to as cover because these sediments obscure the underlying bedrock. Most sedimentary material that fills a basin that is not lithified is typically lumped together as alluvial, alluvium of Pliocene age occurs, for example, in parts of Idaho. Alluvium of late Miocene age occurs, for example, in the valley of the San Joaquin River, alluvium can contain valuable ores such as gold and platinum and a wide variety of gemstones. Such a concentration of ores is termed a placer deposit
2.
Mineral
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A mineral is a naturally occurring chemical compound, usually of crystalline form and abiogenic in origin. A mineral has one specific chemical composition, whereas a rock can be an aggregate of different minerals or mineraloids, the study of minerals is called mineralogy. There are over 5,300 known mineral species, over 5,070 of these have been approved by the International Mineralogical Association, the silicate minerals compose over 90% of the Earths crust. The diversity and abundance of species is controlled by the Earths chemistry. Silicon and oxygen constitute approximately 75% of the Earths crust, which translates directly into the predominance of silicate minerals, minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various species, changes in the temperature, pressure, or bulk composition of a rock mass cause changes in its minerals. Minerals can be described by their various properties, which are related to their chemical structure. Common distinguishing characteristics include crystal structure and habit, hardness, lustre, diaphaneity, colour, streak, tenacity, cleavage, fracture, parting, more specific tests for describing minerals include magnetism, taste or smell, radioactivity and reaction to acid. Minerals are classified by key chemical constituents, the two dominant systems are the Dana classification and the Strunz classification, the silicate class of minerals is subdivided into six subclasses by the degree of polymerization in the chemical structure. All silicate minerals have a unit of a 4− silica tetrahedron—that is, a silicon cation coordinated by four oxygen anions. These tetrahedra can be polymerized to give the subclasses, orthosilicates, disilicates, cyclosilicates, inosilicates, phyllosilicates, other important mineral groups include the native elements, sulfides, oxides, halides, carbonates, sulfates, and phosphates. The first criterion means that a mineral has to form by a natural process, stability at room temperature, in the simplest sense, is synonymous to the mineral being solid. More specifically, a compound has to be stable or metastable at 25 °C, modern advances have included extensive study of liquid crystals, which also extensively involve mineralogy. Minerals are chemical compounds, and as such they can be described by fixed or a variable formula, many mineral groups and species are composed of a solid solution, pure substances are not usually found because of contamination or chemical substitution. Finally, the requirement of an ordered atomic arrangement is usually synonymous with crystallinity, however, crystals are also periodic, an ordered atomic arrangement gives rise to a variety of macroscopic physical properties, such as crystal form, hardness, and cleavage. There have been recent proposals to amend the definition to consider biogenic or amorphous substances as minerals. The formal definition of an approved by the IMA in 1995, A mineral is an element or chemical compound that is normally crystalline. However, if geological processes were involved in the genesis of the compound, Mineral classification schemes and their definitions are evolving to match recent advances in mineral science
3.
Open-pit mining
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Open-pit, open-cast or open cut mining is a surface mining technique of extracting rock or minerals from the earth by their removal from an open pit or borrow. This form of mining differs from extractive methods that require tunneling into the earth, for minerals that occur deep below the surface—where the overburden is thick or the mineral occurs as veins in hard rock—underground mining methods are used to extract the valued material. Open-pit mines that produce building materials and dimension stone are commonly referred to as quarries, open-pit mines are typically enlarged until either the mineral resource is exhausted, or an increasing ratio of overburden to ore makes further mining uneconomic. When this occurs, the mines are sometimes converted to landfills for disposal of solid wastes. Open-cast mines are dug on benches, which describe vertical levels of the hole and these benches are usually on four to sixty meter intervals, depending on the size of the machinery that is being used. Many quarries do not use benches, as they are usually shallow, most walls of the pit are generally blast mined on an angle less than vertical, to prevent and minimize damage and danger from rock falls. This depends on how weathered the rocks are, and the type of rock, the inclined section of the wall is known as the batter, and the flat part of the step is known as the bench or berm. The steps in the walls help prevent rock falls continuing down the face of the wall. In some instances additional ground support is required and rock bolts, cable bolts, de-watering bores may be used to relieve water pressure by drilling horizontally into the wall, which is often enough to cause failures in the wall by itself. A haul road is situated at the side of the pit, forming a ramp up which trucks can drive, carrying ore. Waste rock is piled up at the surface, near the edge of the open pit and this is known as the waste dump. The waste dump is also tiered and stepped, to minimize degradation, ore which has been processed is known as tailings, and is generally a slurry. This is pumped to a dam or settling pond, where the water evaporates. This toxicity can harm the surrounding environment, after mining finishes, the mine area may undergo land rehabilitation. Waste dumps are contoured to flatten out, to further stabilise them. This is then covered with soil, and vegetation is planted to help consolidate the material. There are no long term studies on the success of these due to the relatively short time in which large scale open pit mining has existed. It may take hundreds to thousands of years for some waste dumps to become acid neutral, the dumps are usually fenced off to prevent livestock denuding them of vegetation
4.
Mining
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Mining is extraction of valuable minerals or other geological materials from the earth usually from an orebody, lode, vein, seam, reef or placer deposits. These deposits form a mineralized package that is of economic interest to the miner, ores recovered by mining include metals, coal, oil shale, gemstones, limestone, chalk, dimension stone, rock salt, potash, gravel, and clay. Mining is required to obtain any material that cannot be grown through agricultural processes, Mining in a wider sense includes extraction of any non-renewable resource such as petroleum, natural gas, or even water. Mining of stones and metal has been a human activity since pre-historic times, Mining operations usually create a negative environmental impact, both during the mining activity and after the mine has closed. Hence, most of the nations have passed regulations to decrease the impact. Work safety has long been a concern as well, and modern practices have significantly improved safety in mines, levels of metals recycling are generally low. Unless future end-of-life recycling rates are stepped up, some rare metals may become unavailable for use in a variety of consumer products, due to the low recycling rates, some landfills now contain higher concentrations of metal than mines themselves. Since the beginning of civilization, people have used stone, ceramics and, later and these were used to make early tools and weapons, for example, high quality flint found in northern France, southern England and Poland was used to create flint tools. Flint mines have been found in areas where seams of the stone were followed underground by shafts. The mines at Grimes Graves and Krzemionki are especially famous, other hard rocks mined or collected for axes included the greenstone of the Langdale axe industry based in the English Lake District. The oldest-known mine on archaeological record is the Lion Cave in Swaziland, at this site Paleolithic humans mined hematite to make the red pigment ochre. Mines of an age in Hungary are believed to be sites where Neanderthals may have mined flint for weapons. Ancient Egyptians mined malachite at Maadi, at first, Egyptians used the bright green malachite stones for ornamentations and pottery. Later, between 2613 and 2494 BC, large building projects required expeditions abroad to the area of Wadi Maghareh in order to secure minerals and other resources not available in Egypt itself. Quarries for turquoise and copper were found at Wadi Hammamat, Tura, Aswan and various other Nubian sites on the Sinai Peninsula. Mining in Egypt occurred in the earliest dynasties, the gold mines of Nubia were among the largest and most extensive of any in Ancient Egypt. These mines are described by the Greek author Diodorus Siculus, who mentions fire-setting as one used to break down the hard rock holding the gold. One of the complexes is shown in one of the earliest known maps, the miners crushed the ore and ground it to a fine powder before washing the powder for the gold dust
5.
Precious metal
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A precious metal is a rare, naturally occurring metallic chemical element of high economic value. Chemically, the precious metals tend to be less reactive than most elements and they are usually ductile and have a high lustre. Historically, precious metals were important as currency but are now regarded mainly as investment, Gold, silver, platinum, and palladium each have an ISO4217 currency code. The best known precious metals are the metals, gold. Although both have industrial uses, they are known for their uses in art, jewelry, fine jewelry. Other precious metals include the platinum metals, ruthenium, rhodium, palladium, osmium, iridium. The demand for metals is driven not only by their practical use but also by their role as investments. Historically, precious metals have commanded much higher prices than common industrial metals, a metal is deemed to be precious if it is rare. The discovery of new sources of ore or improvements in mining or refining processes may cause the value of a metal to diminish. The status of a metal can also be determined by high demand or market value. Precious metals in bulk form are known as bullion and are traded on commodity markets, bullion metals may be cast into ingots or minted into coins. The defining attribute of bullion is that it is valued by its mass, the level of purity varies from issue to issue. The purest mass-produced bullion coins are in the Canadian Gold Maple Leaf series, a 100% pure bullion is nearly impossible, as the percentage of impurities diminishes, it becomes progressively more difficult to purify the metal further. Historically, coins had an amount of weight of alloy. The Krugerrand is the first modern example of measuring in pure gold, other bullion coins show neither the purity nor the fine-gold weight on the coin but are recognized and consistent in their composition. Many coins historically showed a denomination in currency, although nominally issued as legal tender, these coins face value as currency is far below that of their value as bullion. For instance, Canada mints a gold coin at a face value of $50 containing one troy ounce of gold—as of May 2011. Bullion coins minting by national governments gives them some numismatic value in addition to their bullion value, one of the largest bullion coins in the world was the 10, 000-dollar Australian Gold Nugget coin minted in Australia which consists of a full kilogram of 99. 9% pure gold
6.
Gold
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Gold is a chemical element with symbol Au and atomic number 79. In its purest form, it is a bright, slightly yellow, dense, soft, malleable. Chemically, gold is a metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions, Gold often occurs in free elemental form, as nuggets or grains, in rocks, in veins, and in alluvial deposits. It occurs in a solid solution series with the element silver and also naturally alloyed with copper. Less commonly, it occurs in minerals as gold compounds, often with tellurium, golds atomic number of 79 makes it one of the higher numbered, naturally occurring elements. It is thought to have produced in supernova nucleosynthesis, from the collision of neutron stars. Because the Earth was molten when it was formed, almost all of the present in the early Earth probably sank into the planetary core. Gold is resistant to most acids, though it does dissolve in aqua regia, a mixture of acid and hydrochloric acid. Gold also dissolves in solutions of cyanide, which are used in mining and electroplating. Gold dissolves in mercury, forming amalgam alloys, but this is not a chemical reaction, as a precious metal, gold has been used for coinage, jewelry, and other arts throughout recorded history. A total of 186,700 tonnes of gold is in existence above ground, the world consumption of new gold produced is about 50% in jewelry, 40% in investments, and 10% in industry. Gold is also used in infrared shielding, colored-glass production, gold leafing, certain gold salts are still used as anti-inflammatories in medicine. As of 2014, the worlds largest gold producer by far was China with 450 tonnes, Gold is cognate with similar words in many Germanic languages, deriving via Proto-Germanic *gulþą from Proto-Indo-European *ǵʰelh₃-. The symbol Au is from the Latin, aurum, the Latin word for gold, the Proto-Indo-European ancestor of aurum was *h₂é-h₂us-o-, meaning glow. This word is derived from the root as *h₂éu̯sōs, the ancestor of the Latin word Aurora. This etymological relationship is presumably behind the frequent claim in scientific publications that aurum meant shining dawn, Gold is the most malleable of all metals, a single gram can be beaten into a sheet of 1 square meter, and an avoirdupois ounce into 300 square feet. Gold leaf can be thin enough to become semi-transparent
7.
Gemstone
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A gemstone is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments. However, certain rocks or organic materials that are not minerals are used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone, apart from jewelry, from earliest antiquity engraved gems and hardstone carvings, such as cups, were major luxury art forms. A gem maker is called a lapidary or gemcutter, a worker is a diamantaire. The carvings of Carl Fabergé are significant works in this tradition, the traditional classification in the West, which goes back to the ancient Greeks, begins with a distinction between precious and semi-precious, similar distinctions are made in other cultures. In modern usage the precious stones are diamond, ruby, sapphire, other stones are classified by their color, translucency and hardness. Another unscientific term for semi-precious gemstones used in art history and archaeology is hardstone, in modern times gemstones are identified by gemologists, who describe gems and their characteristics using technical terminology specific to the field of gemology. The first characteristic a gemologist uses to identify a gemstone is its chemical composition, for example, diamonds are made of carbon and rubies of aluminium oxide. Next, many gems are crystals which are classified by their crystal system such as cubic or trigonal or monoclinic, another term used is habit, the form the gem is usually found in. For example, diamonds, which have a crystal system, are often found as octahedrons. Gemstones are classified into different groups, species, and varieties, for example, ruby is the red variety of the species corundum, while any other color of corundum is considered sapphire. Other examples are the Emerald, aquamarine, red beryl, goshenite, heliodor, and morganite, gems are characterized in terms of refractive index, dispersion, specific gravity, hardness, cleavage, fracture, and luster. They may exhibit pleochroism or double refraction and they may have luminescence and a distinctive absorption spectrum. Material or flaws within a stone may be present as inclusions, gemstones may also be classified in terms of their water. This is a grading of the gems luster, transparency. Very transparent gems are considered first water, while second or third water gems are those of a lesser transparency, there is no universally accepted grading system for gemstones. Diamonds are graded using a system developed by the Gemological Institute of America in the early 1950s, historically, all gemstones were graded using the naked eye
8.
Sand
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Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt, Sand can also refer to a textural class of soil or soil type, i. e. a soil containing more than 85% sand-sized particles by mass. The second most common type of sand is calcium carbonate, for example aragonite, for example, it is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. Sand is a non renewable resource over human timescales, and sand suitable for making concrete is in high demand, in terms of particle size as used by geologists, sand particles range in diameter from 0.0625 mm to 2 mm. An individual particle in this size is termed a sand grain. Sand grains are between gravel and silt, a 1953 engineering standard published by the American Association of State Highway and Transportation Officials set the minimum sand size at 0.074 mm. A1938 specification of the United States Department of Agriculture was 0.05 mm. Sand feels gritty when rubbed between the fingers. ISO14688 grades sands as fine, medium and coarse with ranges 0.063 mm to 0.2 mm to 0.63 mm to 2.0 mm. In the United States, sand is commonly divided into five sub-categories based on size, very fine sand, fine sand, medium sand, coarse sand, and very coarse sand. These sizes are based on the Krumbein phi scale, where size in Φ = -log2D, on this scale, for sand the value of Φ varies from −1 to +4, with the divisions between sub-categories at whole numbers. The composition of sand is highly variable, depending on the local rock sources. The gypsum sand dunes of the White Sands National Monument in New Mexico are famous for their bright, arkose is a sand or sandstone with considerable feldspar content, derived from weathering and erosion of a granitic rock outcrop. Some sands contain magnetite, chlorite, glauconite or gypsum, Sands rich in magnetite are dark to black in color, as are sands derived from volcanic basalts and obsidian. Chlorite-glauconite bearing sands are typically green in color, as are sands derived from basaltic with a high olivine content, many sands, especially those found extensively in Southern Europe, have iron impurities within the quartz crystals of the sand, giving a deep yellow color. Sand deposits in some areas contain garnets and other resistant minerals, the study of individual grains can reveal much historical information as to the origin and kind of transport of the grain. Quartz sand that is weathered from granite or gneiss quartz crystals will be angular. It is called grus in geology or sharp sand in the trade where it is preferred for concrete. Sand that is transported long distances by water or wind will be rounded, people who collect sand as a hobby are known as arenophiles
9.
Hydraulic mining
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Hydraulic mining, or hydraulicking, is a form of mining that uses high-pressure jets of water to dislodge rock material or move sediment. In the placer mining of gold or tin, the resulting water-sediment slurry is directed through sluice boxes to remove the gold and it is also used in mining kaolin and coal. Hydraulic mining originated out of ancient Roman techniques that used water to excavate soft underground deposits and its modern form, using pressurized water jets produced by a nozzle called a monitor, came about in the 1850s during the California Gold Rush in the United States. These problems led to its legal regulation, Hydraulic mining has since been used in various forms around the world. The method was used in Elizabethan England & Wales for developing lead, tin. Water was used on a large scale by Roman engineers in the first centuries BC, using a process later known as hushing, the Romans stored a large volume of water in a reservoir immediately above the area to be mined, the water was then quickly released. The resulting wave of water removed overburden and exposed bedrock, Gold veins in the bedrock were then worked using a number of techniques, and water power was used again to remove debris. The remains at Las Medulas and in surrounding areas show badland scenery on a gigantic scale owing to hydraulicking of the alluvial gold deposits. Las Medulas is now a UNESCO World Heritage site, the site shows the remains of at least seven large aqueducts of up to 30 miles in length feeding large supplies of water into the site. The gold-mining operations were described in vivid terms by Pliny the Elder in his Naturalis Historia published in the first century AD, Pliny was a procurator in Hispania Terraconensis in the 70s and must have witnessed for himself the operations. The use of hushing has been confirmed by field survey and archaeology at Dolaucothi in South Wales, matteson used canvas hose which was later replaced with crinoline hose by the 1860s. In California, hydraulic mining often brought water from higher locations for long distances to holding several hundred feet above the area to be mined. California hydraulic mining exploited gravel deposits, making it a form of placer mining, early placer miners in California discovered that the more gravel they could process, the more gold they were likely to find. Instead of working with pans, sluice boxes, long toms, Hydraulic mining became the largest-scale, and most devastating, form of placer mining. Water was redirected into a channel, through a large canvas hose. The extremely high pressure stream was used to wash entire hillsides through enormous sluices, by the mid-1880s, it is estimated that 11 million ounces of gold had been recovered by hydraulic mining in the California Gold Rush. Millions of tons of earth and water were delivered to mountain streams that fed rivers flowing into the Sacramento Valley, cities and towns in the Sacramento Valley experienced an increasing number of devastating floods, while the rising riverbeds made navigation on the rivers increasingly difficult. Perhaps no other city experienced the boon and the bane of gold mining as much as Marysville, situated at the confluence of the Yuba and Feather rivers, Marysville was the final jumping off point for miners heading to the northern foothills to seek their fortune
10.
Sluice
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A sluice is a water channel controlled at its head by a gate. A mill race, leet, flume, penstock or lade is a sluice channelling water toward a water mill, the terms sluice, sluice gate, knife gate, and slide gate are used interchangeably in the water and wastewater control industry. A sluice gate is traditionally a wood or metal barrier sliding in grooves that are set in the sides of the waterway, Sluice gates commonly control water levels and flow rates in rivers and canals. They are also used in treatment plants and to recover minerals in mining operations. Sluice gate refers to a gate allowing water to flow under it. When a sluice is lowered, water may spill over the top, usually, a mechanism drives the sluice up or down. This may be a simple, hand-operated, chain pulled/lowered, worm drive or rack-and-pinion drive, flap sluice gate A fully automatic type, controlled by the pressure head across it, operation is similar to that of a check valve. It is a gate hinged at the top, when pressure is from one side, the gate is kept closed, a pressure from the other side opens the sluice when a threshold pressure is surpassed. Vertical rising sluice gate A plate sliding in the vertical direction, radial sluice gate A structure, where a small part of a cylindrical surface serves as the gate, supported by radial constructions going through the cylinders radius. On occasion, a counterweight is provided, rising sector sluice gate Also a part of a cylindrical surface, which rests at the bottom of the channel and rises by rotating around its centre. Needle sluice A sluice formed by a number of thin needles held against a solid frame through water pressure as in a needle dam. The gates of a Guillotine lock work in a way similar to a sluice gate, in the mountains of the United States, sluices transported logs from steep hillsides to downslope sawmill ponds or yarding areas. Nineteenth-century logging was traditionally a winter activity for men who spent summers working on farms, where there were freezing nights, water might be applied to logging sluices every night so a fresh coating of slippery ice would reduce friction of logs placed in the sluice the following morning. Sluice boxes are used in the recovery of black sands, gold. They may be small-scale, as used in prospecting, or much larger, as in commercial operations, typical sluices have transverse riffles over a carpet, which trap the heavy minerals, gemstones, and other valuable minerals. Cast Iron Cast iron has been popular when constructing sluice gates for years and this material is great at keeping the strength needed when dealing with powerful water levels. Stainless Steel Stainless steel in most cases is lighter than the older cast iron material, fibre-reinforced plastic Rather recently a new technologies such as fibre-reinforced plastic are being used to build sluices. This modern technology has many of the attributes as the older ways while bringing in new attributes such as corrosion resistance, in the Somerset Levels, sluice gates are known as clyse or clyce
11.
Medieval Latin
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Despite the clerical origin of many of its authors, medieval Latin should not be confused with Ecclesiastical Latin. There is no consensus on the exact boundary where Late Latin ends. Medieval Latin had a vocabulary, which freely borrowed from other sources. Greek provided much of the vocabulary of Christianity. The various Germanic languages spoken by the Germanic tribes, who invaded southern Europe, were major sources of new words. Germanic leaders became the rulers of parts of the Roman Empire that they conquered, other more ordinary words were replaced by coinages from Vulgar Latin or Germanic sources because the classical words had fallen into disuse. Latin was also spread to such as Ireland and Germany. Works written in the lands, where Latin was a language with no relation to the local vernacular, also influenced the vocabulary. English words like abstract, subject, communicate, matter, probable, the high point of the development of medieval Latin as a literary language came with the Carolingian renaissance, a rebirth of learning kindled under the patronage of Charlemagne, king of the Franks. On the other hand, strictly speaking there was no form of medieval Latin. Every Latin author in the period spoke Latin as a second language, with varying degrees of fluency, and syntax, grammar. For instance, rather than following the classical Latin practice of placing the verb at the end. Unlike classical Latin, where esse was the auxiliary verb, medieval Latin writers might use habere as an auxiliary, similar to constructions in Germanic. The accusative and infinitive construction in classical Latin was often replaced by a clause introduced by quod or quia. This is almost identical, for example, to the use of que in similar constructions in French. In every age from the late 8th century onwards, there were learned writers who were familiar enough with classical syntax to be aware that these forms and usages were wrong, however the use of quod to introduce subordinate clauses was especially pervasive and is found at all levels. That resulted in two features of Medieval Latin compared with Classical Latin. First, many attempted to show off their knowledge of Classical Latin by using rare or archaic constructions
12.
De re metallica
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De re metallica is a book cataloguing the state of the art of mining, refining, and smelting metals, published a year posthumously in 1556 due to a delay in preparing woodcuts for the text. The author was Georg Bauer, whose pen name was the Latinized Georgius Agricola, the book remained the authoritative text on mining for 180 years after its publication. It was also an important chemistry text for the period and is significant in the history of chemistry, mining was typically left to professionals, craftsmen and experts who were not eager to share their knowledge. Much experiential knowledge had been accumulated over the course of time and this knowledge was consecutively handed down orally within a small group of technicians and mining overseers. In the Middle Ages these people held the leading role as the master builders of the great cathedrals. It was a small, cosmopolitan elite within which existing knowledge was passed on and further developed, only a few writers from that time wrote anything about mining itself. Partly, that was because this knowledge was very difficult to access, most writers also found it simply not worth the effort to write about it. Only in the Renaissance did this begin to change. With the improved transport and the invention of the printing press knowledge spread much more easily, in 1500, the first printed book dedicated to mining engineering, called the “Nutzlich Bergbuchleyn” by Ulrich Rulein von Calw, was published. The most important works in this genre were, however, the twelve books De Re Metallica by Georgius Agricola, Agricola had spent nine years in the Bohemian town of Joachimsthal, now in the Czech Republic. After Joachimsthal, he spent the rest of his life in Chemnitz, both Joachimsthal and Chemnitz are in the Erzgebirge, or Ore Mountains. The book was influential, and for more than a century after it was published. The German mining technology it portrayed was acknowledged as the most advanced at the time, the book was reprinted in a number of Latin editions, as well as in German and Italian translations. Publication in Latin meant that it could be read by any educated European of the time, the numerous woodcuts and detailed descriptions of machinery made it a practical reference for those wishing to replicate the latest in mining technology. In 1912, the first English translation of De Re Metallica was privately published in London by subscription, the translators were Herbert Hoover, a mining engineer, and his wife, Lou Henry Hoover, a geologist and Latinist. The translation is not only for its clarity of language, but for the extensive footnotes. The most important translation—outside English—was the one published by the Deutsches Museum in Munich The book consists of a preface and twelve chapters, labelled books I to XII and it also has numerous woodcuts that provide annotated diagrams illustrating equipment and processes described in the text. Agricola addresses the book to prominent German aristocrats, the most important of whom were Maurice, Elector of Saxony and his brother Augustus and he then describes the works of ancient and contemporary writers on mining and metallurgy, the chief ancient source being Pliny the Elder
