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112-794: Reconstructions of the botanical vocabulary offer clues to the ecological niche inhabited by the Proto-Uto-Aztecans. Fowler placed the center of Proto-Uto-Aztecan in Central Arizona with northern dialects extending into Nevada and the Mojave desert and southern dialects extending south through the Tepiman corridor into Mexico. The homeland of the Numic languages has been placed in Southern California near Death Valley , and

224-486: A bullet cast from silver is often supposed in such folklore the only weapon that is effective against a werewolf , witch , or other monsters . From this the idiom of a silver bullet developed into figuratively referring to any simple solution with very high effectiveness or almost miraculous results, as in the widely discussed software engineering paper " No Silver Bullet ." Other powers attributed to silver include detection of poison and facilitation of passage into

336-419: A color name . Protected silver has greater optical reflectivity than aluminium at all wavelengths longer than ~450 nm. At wavelengths shorter than 450 nm, silver's reflectivity is inferior to that of aluminium and drops to zero near 310 nm. Very high electrical and thermal conductivity are common to the elements in group 11, because their single s electron is free and does not interact with

448-470: A precious metal . Silver metal is used in many bullion coins , sometimes alongside gold : while it is more abundant than gold, it is much less abundant as a native metal . Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity , silver has had an enduring role in most human cultures. Other than in currency and as an investment medium ( coins and bullion ), silver

560-475: A diversity of flora and fauna. The 54,000 sq mi (140,000 km ) desert supports a number of human activities, including recreation, ranching, and military training. The Mojave Desert also contains various silver , tungsten , iron and gold deposits. The spelling Mojave originates from the Spanish language, while the spelling Mohave comes from modern English. Both are used today, although

672-595: A fuel bed. This has significantly altered many areas of the desert. At higher elevations, fire regimes are regular but infrequent. While the Mojave Desert is generally sparsely populated, it has increasingly become urbanized in recent years. The metropolitan areas include Las Vegas , the largest urban area in the Mojave and the largest urban area in Nevada with a population of about 2.3 million. St. George, Utah ,

784-406: A long-running dispute over the proper reconstruction. *n and *ŋ may have actually been *l and *n . The following are selected Proto-Uto-Aztecan reconstructions from Stubbs (2011). Mojave Desert The Mojave Desert ( / m oʊ ˈ h ɑː v i , m ə -/ ; Mohave : Hayikwiir Mat'aar ; Spanish : Desierto de Mojave ) is a desert in the rain shadow of

896-406: A natural border to the Mojave Desert. There are also abundant alluvial fans , which are called bajadas , that form around the mountains within the Mojave Desert and extend down toward the low altitude basins, which contain dried lake beds called playas, where water generally collects and evaporates, leaving large volumes of salt. These playas include Rogers Dry Lake and China Lake . Dry lakes are

1008-592: A non-Indo-European Wanderwort . Some scholars have thus proposed a Paleo-Hispanic origin, pointing to the Basque form zilharr as an evidence. The chemical symbol Ag is from the Latin word for silver , argentum (compare Ancient Greek ἄργυρος , árgyros ), from the Proto-Indo-European root * h₂erǵ- (formerly reconstructed as *arǵ- ), meaning ' white ' or ' shining ' . This

1120-709: A noted feature of the Mojave landscape. The Mojave Desert is also home to the Devils Playground , about 40 miles (64 km) of dunes and salt flats going in a northwest-southeasterly direction. The Devil's Playground is a part of the Mojave National Preserve and is between the town of Baker, California and the Providence Mountains . The Cronese Mountains are within the Devil's Playground. There are very few surface rivers in

1232-614: A reward for betrayal, references the bribe Judas Iscariot is said in the New Testament to have taken from Jewish leaders in Jerusalem to turn Jesus of Nazareth over to soldiers of the high priest Caiaphas. Ethically, silver also symbolizes greed and degradation of consciousness; this is the negative aspect, the perverting of its value. The abundance of silver in the Earth's crust is 0.08  parts per million , almost exactly

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1344-629: A scale unparalleled before the discovery of the New World . Reaching a peak production of 200 tonnes per year, an estimated silver stock of 10,000 tonnes circulated in the Roman economy in the middle of the second century AD, five to ten times larger than the combined amount of silver available to medieval Europe and the Abbasid Caliphate around AD 800. The Romans also recorded the extraction of silver in central and northern Europe in

1456-407: A single electron in the highest occupied s subshell over a filled d subshell, accounts for many of the singular properties of metallic silver. Silver is a relatively soft and extremely ductile and malleable transition metal , though it is slightly less malleable than gold. Silver crystallizes in a face-centered cubic lattice with bulk coordination number 12, where only the single 5s electron

1568-567: Is cognate with Old High German silabar ; Gothic silubr ; or Old Norse silfr , all ultimately deriving from Proto-Germanic *silubra . The Balto-Slavic words for silver are rather similar to the Germanic ones (e.g. Russian серебро [ serebró ], Polish srebro , Lithuanian sidãbras ), as is the Celtiberian form silabur . They may have a common Indo-European origin, although their morphology rather suggest

1680-465: Is the difluoride , AgF 2 , which can be obtained from the elements under heat. A strong yet thermally stable and therefore safe fluorinating agent, silver(II) fluoride is often used to synthesize hydrofluorocarbons . In stark contrast to this, all four silver(I) halides are known. The fluoride , chloride , and bromide have the sodium chloride structure, but the iodide has three known stable forms at different temperatures; that at room temperature

1792-470: Is Ag 3 O which behaves as a metallic conductor. Silver(I) sulfide , Ag 2 S, is very readily formed from its constituent elements and is the cause of the black tarnish on some old silver objects. It may also be formed from the reaction of hydrogen sulfide with silver metal or aqueous Ag ions. Many non-stoichiometric selenides and tellurides are known; in particular, AgTe ~3 is a low-temperature superconductor . The only known dihalide of silver

1904-588: Is a former ranch along the Mojave River. Several attractions and natural features are in the Calico Mountains . Calico Ghost Town , in Yermo, is administered by San Bernardino County. The ghost town has several shops and attractions and inspired Walter Knott to build Knott's Berry Farm . The Bureau of Land Management also administers Rainbow Basin and Owl Canyon. The Calico Early Man Site , in

2016-438: Is because its filled 4d shell is not very effective in shielding the electrostatic forces of attraction from the nucleus to the outermost 5s electron, and hence silver is near the bottom of the electrochemical series ( E (Ag /Ag) = +0.799 V). In group 11, silver has the lowest first ionization energy (showing the instability of the 5s orbital), but has higher second and third ionization energies than copper and gold (showing

2128-425: Is delocalized, similarly to copper and gold. Unlike metals with incomplete d-shells, metallic bonds in silver are lacking a covalent character and are relatively weak. This observation explains the low hardness and high ductility of single crystals of silver. Silver has a brilliant, white, metallic luster that can take a high polish , and which is so characteristic that the name of the metal itself has become

2240-473: Is generally abundant in winter annuals. The plants of the Mojave Desert each generally correspond to an individual geographic feature. As such, there are distinctive flora communities within the desert. Notable species of the Mojave Desert include bighorn sheep ( Ovis canadensis ), mountain lions ( Puma concolor ), black-tailed jackrabbits ( Lepus californicus ), and desert tortoises ( Gopherus agassizii ). Various other species are particularly common in

2352-549: Is higher than that of lead (1.87), and its electron affinity of 125.6 kJ/mol is much higher than that of hydrogen (72.8 kJ/mol) and not much less than that of oxygen (141.0 kJ/mol). Due to its full d-subshell, silver in its main +1 oxidation state exhibits relatively few properties of the transition metals proper from groups 4 to 10, forming rather unstable organometallic compounds , forming linear complexes showing very low coordination numbers like 2, and forming an amphoteric oxide as well as Zintl phases like

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2464-413: Is much less stable, fuming in moist air and reacting with glass. Silver(II) complexes are more common. Like the valence isoelectronic copper(II) complexes, they are usually square planar and paramagnetic, which is increased by the greater field splitting for 4d electrons than for 3d electrons. Aqueous Ag , produced by oxidation of Ag by ozone, is a very strong oxidising agent, even in acidic solutions: it

2576-572: Is not endemic, but almost completely limited to the Mojave Desert. There are also aquatic species that are found nowhere else, such as the Devils Hole pupfish , limited to one hot spring near Death Valley. Before the European colonization of North America, tribes of Native Americans, such as the Mohave , were hunter-gatherers living in the Mojave Desert. European explorers started exploring

2688-410: Is not reversible because the silver atom liberated is typically found at a crystal defect or an impurity site, so that the electron's energy is lowered enough that it is "trapped". White silver nitrate , AgNO 3 , is a versatile precursor to many other silver compounds, especially the halides, and is much less sensitive to light. It was once called lunar caustic because silver was called luna by

2800-424: Is pale yellow, becoming purplish on exposure to light; it projects slightly from the surface of the artifact or coin. The precipitation of copper in ancient silver can be used to date artifacts, as copper is nearly always a constituent of silver alloys. Silver metal is attacked by strong oxidizers such as potassium permanganate ( KMnO 4 ) and potassium dichromate ( K 2 Cr 2 O 7 ), and in

2912-415: Is rare in the periodic table. The atomic weight is 107.8682(2) u ; this value is very important because of the importance of silver compounds, particularly halides, in gravimetric analysis . Both isotopes of silver are produced in stars via the s-process (slow neutron capture), as well as in supernovas via the r-process (rapid neutron capture). Twenty-eight radioisotopes have been characterized,

3024-536: Is reflected in the relative decomposition temperatures of AgMe (−50 °C) and CuMe (−15 °C) as well as those of PhAg (74 °C) and PhCu (100 °C). The C–Ag bond is stabilized by perfluoroalkyl ligands, for example in AgCF(CF 3 ) 2 . Alkenylsilver compounds are also more stable than their alkylsilver counterparts. Silver- NHC complexes are easily prepared, and are commonly used to prepare other NHC complexes by displacing labile ligands. For example,

3136-430: Is similar in its physical and chemical properties to its two vertical neighbours in group 11 of the periodic table : copper , and gold . Its 47 electrons are arranged in the configuration [Kr]4d 5s , similarly to copper ([Ar]3d 4s ) and gold ([Xe]4f 5d 6s ); group 11 is one of the few groups in the d-block which has a completely consistent set of electron configurations. This distinctive electron configuration, with

3248-472: Is stabilized in phosphoric acid due to complex formation. Peroxodisulfate oxidation is generally necessary to give the more stable complexes with heterocyclic amines , such as [Ag(py) 4 ] and [Ag(bipy) 2 ] : these are stable provided the counterion cannot reduce the silver back to the +1 oxidation state. [AgF 4 ] is also known in its violet barium salt, as are some silver(II) complexes with N - or O -donor ligands such as pyridine carboxylates. By far

3360-413: Is the cubic zinc blende structure. They can all be obtained by the direct reaction of their respective elements. As the halogen group is descended, the silver halide gains more and more covalent character, solubility decreases, and the colour changes from the white chloride to the yellow iodide as the energy required for ligand-metal charge transfer (X Ag → XAg) decreases. The fluoride is anomalous, as

3472-643: Is the northeasternmost metropolitan area in the Mojave, with a population of around 180,000 in 2020, and is located at the convergence of the Mojave, Great Basin, and Colorado Plateau. The Los Angeles exurban area of Lancaster - Palmdale has more than 400,000 residents, and the Victorville area to its east has more than 300,000 residents. Smaller cities or micropolitan areas in the Mojave Desert include Helendale , Lake Havasu City , Kingman , Laughlin , Bullhead City and Pahrump . All have experienced rapid population growth since 1990. The California portion of

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3584-406: Is the principal saline basin of the Mojave Desert. Natural springs are typically rare throughout the Mojave Desert, but there are two notable springs, Ash Meadows and Oasis Valley . Ash Meadows is formed from several other springs, which all draw from deep underground. Oasis Valley draws from the nearby Amargosa River. Extremes in temperatures throughout the seasons characterize the climate of

3696-614: Is used in solar panels , water filtration , jewellery , ornaments, high-value tableware and utensils (hence the term " silverware "), in electrical contacts and conductors , in specialized mirrors, window coatings, in catalysis of chemical reactions, as a colorant in stained glass , and in specialized confectionery. Its compounds are used in photographic and X-ray film. Dilute solutions of silver nitrate and other silver compounds are used as disinfectants and microbiocides ( oligodynamic effect ), added to bandages , wound-dressings, catheters , and other medical instruments . Silver

3808-726: Is used in vacuum brazing . The two metals are completely miscible as liquids but not as solids; their importance in industry comes from the fact that their properties tend to be suitable over a wide range of variation in silver and copper concentration, although most useful alloys tend to be richer in silver than the eutectic mixture (71.9% silver and 28.1% copper by weight, and 60.1% silver and 28.1% copper by atom). Most other binary alloys are of little use: for example, silver–gold alloys are too soft and silver– cadmium alloys too toxic. Ternary alloys have much greater importance: dental amalgams are usually silver–tin–mercury alloys, silver–copper–gold alloys are very important in jewellery (usually on

3920-482: Is usually obtained by reacting silver or silver monofluoride with the strongest known oxidizing agent, krypton difluoride . Silver and gold have rather low chemical affinities for oxygen, lower than copper, and it is therefore expected that silver oxides are thermally quite unstable. Soluble silver(I) salts precipitate dark-brown silver(I) oxide , Ag 2 O, upon the addition of alkali. (The hydroxide AgOH exists only in solution; otherwise it spontaneously decomposes to

4032-848: The Koenigs–Knorr reaction . In the Fétizon oxidation , silver carbonate on celite acts as an oxidising agent to form lactones from diols . It is also employed to convert alkyl bromides into alcohols . Silver fulminate , AgCNO, a powerful, touch-sensitive explosive used in percussion caps , is made by reaction of silver metal with nitric acid in the presence of ethanol . Other dangerously explosive silver compounds are silver azide , AgN 3 , formed by reaction of silver nitrate with sodium azide , and silver acetylide , Ag 2 C 2 , formed when silver reacts with acetylene gas in ammonia solution. In its most characteristic reaction, silver azide decomposes explosively, releasing nitrogen gas: given

4144-545: The Lahn region, Siegerland , Silesia , Hungary , Norway , Steiermark , Schwaz , and the southern Black Forest . Most of these ores were quite rich in silver and could simply be separated by hand from the remaining rock and then smelted; some deposits of native silver were also encountered. Many of these mines were soon exhausted, but a few of them remained active until the Industrial Revolution , before which

4256-664: The Mojave Tribal Nation officially uses the spelling Mojave . Mojave is a shortened form of Hamakhaave , an endonym in their native language, which means "beside the water". The Mojave Desert is a desert bordered to the west by the Sierra Nevada mountain range and the California montane chaparral and woodlands , and to the south and east by the Sonoran Desert. The boundaries to the east of

4368-549: The Mojave National Preserve . However, the southwest and central east portions of the Mojave Desert are particularly threatened as a result of off-road vehicles, increasing recreational use, human development, and agricultural grazing . The World Wildlife Fund lists the Mojave Desert as relatively "stable/intact". Various habitats and regions of the Mojave Desert have been protected by statute. Notably, Joshua Tree National Park, Death Valley National Park, and

4480-555: The Oligocene . Large downpours during the Miocene likely significantly eroded the rock in the Mojave and accelerated deposition . The Mojave Desert is a source of various minerals and metallic materials. Due to the climate, there is an accumulation of weathered bedrock, fine sand and silt, both sand and silt sediments becoming converted into colluvium . The deposits of gold, tungsten, and silver have been mined frequently prior to

4592-577: The Paleozoic era, the area that is now the Mojave was again likely submerged under a greater sea. During the Mesozoic era, major tectonic activities such as thrust faulting and folding resulted in distinctive shaping as well as intrusion . During the Cenozoic , more tectonic deformation occurred whilst the Mojave was partly submerged. Major volcanic activity is thought to have occurred during

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4704-478: The San Gabriel Mission . In recent years, human development in the Mojave Desert has become increasingly present. Human development at the major urban and suburban centers of Las Vegas and Los Angeles has had an increasingly damaging effect on the wildlife of the Mojave Desert. An added demand for landfill space as a result of the large metropolitan centers of Las Vegas and Los Angeles also has

4816-535: The Second World War . Additionally, there have been deposits of copper , tin , lead-zinc , manganese , iron , and various radioactive substances but they have not been mined for commercial use. The flora of the Mojave Desert consists of various endemic plant species, notably the Joshua Tree , which is a notable endemic and indicator species of the desert. There is more endemic flora in

4928-460: The Yokutsan languages . That leads Shaul to suggest that Proto-Uto-Aztecan was spoken in California's Central Valley area , and it formed part of an ancient Californian linguistic area . Proto-Uto-Aztecan is reconstructed as having an unusual vowel inventory: *i *a *u *o *ɨ . Langacker (1970) demonstrated that the fifth vowel should be reconstructed as *ɨ as opposed to *e , and there has been

5040-666: The mythical realm of fairies . Silver production has also inspired figurative language. Clear references to cupellation occur throughout the Old Testament of the Bible , such as in Jeremiah 's rebuke to Judah: "The bellows are burned, the lead is consumed of the fire; the founder melteth in vain: for the wicked are not plucked away. Reprobate silver shall men call them, because the Lord hath rejected them." (Jeremiah 6:19–20) Jeremiah

5152-435: The platinum complexes (though they are formed more readily than those of the analogous gold complexes): they are also quite unsymmetrical, showing the weak π bonding in group 11. Ag–C σ bonds may also be formed by silver(I), like copper(I) and gold(I), but the simple alkyls and aryls of silver(I) are even less stable than those of copper(I) (which tend to explode under ambient conditions). For example, poor thermal stability

5264-526: The post-transition metals . Unlike the preceding transition metals, the +1 oxidation state of silver is stable even in the absence of π-acceptor ligands . Silver does not react with air, even at red heat, and thus was considered by alchemists as a noble metal , along with gold. Its reactivity is intermediate between that of copper (which forms copper(I) oxide when heated in air to red heat) and gold. Like copper, silver reacts with sulfur and its compounds; in their presence, silver tarnishes in air to form

5376-731: The 19th century, primary production of silver moved to North America, particularly Canada , Mexico , and Nevada in the United States : some secondary production from lead and zinc ores also took place in Europe, and deposits in Siberia and the Russian Far East as well as in Australia were mined. Poland emerged as an important producer during the 1970s after the discovery of copper deposits that were rich in silver, before

5488-820: The Calico Hills east of Yermo , is believed by some archaeologists, including the late Louis Leakey , to show the earliest evidence with lithic stone tools found here of human activity in North America. The Mojave Desert has a relatively stable and intact conservation status. The Mojave Desert is one of the best protected distinct ecoregions in the United States, as a result of the California Desert Protection Act , which designated 69 wilderness areas and established Death Valley National Park , Joshua Tree National Park , and

5600-576: The Greek and Roman civilizations, silver coins were a staple of the economy: the Greeks were already extracting silver from galena by the 7th century BC, and the rise of Athens was partly made possible by the nearby silver mines at Laurium , from which they extracted about 30 tonnes a year from 600 to 300 BC. The stability of the Roman currency relied to a high degree on the supply of silver bullion, mostly from Spain, which Roman miners produced on

5712-724: The Joshua tree (Yucca brevifolia). Additionally, the Mojave Desert is also home to various species of cacti, such as silver cholla ( Cylindropuntia echinocarpa ), Mojave prickly pear ( O. erinacea ), beavertail cactus ( O. basilaris ), and many-headed barrel cactus ( Echinocactus polycephalus ). Less common but distinctive plants of the Mojave Desert include ironwood ( Olneya tesota ), blue Palo Verde ( Parkinsonia Florida ), chuparosa ( Justicia californica ), spiny menodora ( Menodora spinescens ), desert senna ( Cassia armata ), California dalea ( Psorothamnus arborescens ), and goldenhead ( Acamptopappus shockleyi ). The Mojave Desert

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5824-807: The Mojave Desert are less distinctive than the other boundaries because there is no presence of an indicator species, such as the Joshua tree ( Yucca brevifolia ), which is endemic to the Mojave Desert. The Mojave Desert is distinguished from the Sonoran Desert and other deserts adjacent to it by its warm temperate climate, as well as flora and fauna such as ironwood ( Olneya tesota ), blue Palo Verde ( Parkinsonia florida ), chuparosa ( Justicia californica ), spiny menodora ( Menodora spinescens ), desert senna ( Cassia armata ), California dalea ( Psorothamnus arborescens ), California fan palm (Washingtonia filifera) and goldenhead ( Acamptopappus shockleyi ). Along with these other factors, these plants differentiate

5936-585: The Mojave Desert in the San Gabriel mountains may receive more rain. Most of the precipitation in the Mojave comes from the Pacific Cyclonic storms that are generally present passing eastward in November to April. Such storms generally bring rain and snow only in the mountainous regions, as a result of the effect of the mountains, which creates a drying effect on its leeward slopes . During

6048-629: The Mojave Desert than almost anywhere in the world. Mojave Desert flora is not a vegetation type , although the plants in the area have evolved in isolation because of the physical barriers of the Sierra Nevadas and the Colorado Plateau. Predominant plants of the Mojave Desert include all-scale ( Atriplex polycarpa ), creosote bush ( Larrea tridentata ), brittlebush ( Encelia farinosa ), desert holly ( Atriplex hymenelytra ), white burrobush (Hymenoclea salsola), and most notably,

6160-725: The Mojave Desert was further protected from development by the Desert Renewable Energy Conservation Plan (DRECP), in which the Bureau of Land Management designated 4.2 million acres of public land as protected wilderness as part of the National Conservation Lands of the California Desert. The Mojave Desert has served as a backdrop for a number of films . The 2010 video game Fallout: New Vegas takes place in

6272-596: The Mojave Desert, but two major rivers generally flow underground. One is the intermittent Mojave River , which begins in the San Bernardino mountains and disappears underground in the Mojave Desert. The other is the Amargosa River , which flows partly underground through the Mojave Desert along a southward path. The Manix, Mojave, and the Little Mojave lakes are all large but shallow. Soda Lake

6384-609: The Mojave Desert, or "Mojave Wasteland" as it is known in its post-apocalyptic future. At least seven music videos were recorded in the Mojave Desert: Photographs related to U2 's 1987 album The Joshua Tree were taken in the Mojave Desert. Silver Silver is a chemical element ; it has symbol Ag (from Latin argentum  'silver', derived from Proto-Indo-European *h₂erǵ ' shiny, white ' ) and atomic number 47. A soft, white, lustrous transition metal , it exhibits

6496-495: The Mojave Desert, such as the LeConte's thrasher ( Toxostoma lecontei ), banded gecko ( Coleonyx variegatus ), desert iguana (Dipsosaurus dorsalis), chuckwalla ( Sauromalus obesus ), and regal horned lizard ( Phrynosoma solare ). Species of snake include the rosy boa ( Lichanura trivirgata ), Western patch-nosed snake ( Salvadora hexalepis ), and Mojave rattlesnake ( Crotalus scutulatus ). These species can also occur in

6608-399: The Mojave Desert. Freezing temperatures as well as strong winds are not uncommon in the winter, as well as precipitation such as rain and snow in the mountains. In contrast, temperatures above 100 °F (38 °C) are not uncommon during the summer months. There is an annual average precipitation of 2 to 6 inches (51 to 152 mm), although regions at high altitudes such as the portion of

6720-793: The Mojave National Preserve by the California Desert Protection Act of 1994. ( Pub.L. 103–433). Various other federal and state land agencies have protected regions within the Mojave Desert. These include Antelope Valley California Poppy Reserve , which protects the fields of California poppies, Mojave Trails National Monument , Desert Tortoise Natural Area , Arthur B. Ripley Desert Woodland State Park , Desert National Wildlife Refuge , Lake Mead National Recreation Area , Providence Mountains State Recreation Area , Red Cliffs National Conservation Area , Red Rock Canyon State Park , Saddleback Butte State Park , Snow Canyon State Park and Valley of Fire State Park . In 2013,

6832-737: The Mojave a critical training location for the United States Department of Defense. The Mojave Desert has long been a valuable resource for people, and as its human population grows, its importance will only grow. Miners, ranchers, and farmers rely on the desert for a living. The Mojave is also used by the state of California to meet renewable energy objectives. Large tracts of the desert are owned by federal agencies and are leased at low cost by wind and solar energy companies, although these renewable developments can cause their own environmental impact and disturb cultural landscapes and visual resources. Desert Sunlight Solar Farm , one of

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6944-600: The Mojave from the nearby Sonoran Desert. The Mojave Desert is bordered by the San Andreas Fault to the southwest and the Garlock fault to the north. The mountains elevated along the length of the San Andreas fault provide a clear border between the Mojave Desert and the coastal regions to the west. The Garlock fault separates the Mojave Desert from the Sierra Nevada and Tehachapi mountains, which provide

7056-405: The Mojave is the smallest and driest. It displays typical basin and range topography , generally having a pattern of a series of parallel mountain ranges and valleys. It is also the site of Death Valley , which is the lowest elevation in North America. The Mojave Desert is often colloquially called the "high desert", as most of it lies between 2,000 and 4,000 feet (610 and 1,220 m). It supports

7168-449: The US, 13540 tons of silver were used for the electromagnets in calutrons for enriching uranium , mainly because of the wartime shortage of copper. Silver readily forms alloys with copper, gold, and zinc . Zinc-silver alloys with low zinc concentration may be considered as face-centred cubic solid solutions of zinc in silver, as the structure of the silver is largely unchanged while

7280-557: The ancient alchemists, who believed that silver was associated with the Moon. It is often used for gravimetric analysis, exploiting the insolubility of the heavier silver halides which it is a common precursor to. Silver nitrate is used in many ways in organic synthesis , e.g. for deprotection and oxidations. Ag binds alkenes reversibly, and silver nitrate has been used to separate mixtures of alkenes by selective absorption. The resulting adduct can be decomposed with ammonia to release

7392-637: The black silver sulfide (copper forms the green sulfate instead, while gold does not react). While silver is not attacked by non-oxidizing acids, the metal dissolves readily in hot concentrated sulfuric acid , as well as dilute or concentrated nitric acid . In the presence of air, and especially in the presence of hydrogen peroxide , silver dissolves readily in aqueous solutions of cyanide . The three main forms of deterioration in historical silver artifacts are tarnishing, formation of silver chloride due to long-term immersion in salt water, as well as reaction with nitrate ions or oxygen. Fresh silver chloride

7504-712: The centre of production returned to the Americas the following decade. Today, Peru and Mexico are still among the primary silver producers, but the distribution of silver production around the world is quite balanced and about one-fifth of the silver supply comes from recycling instead of new production. Silver plays a certain role in mythology and has found various usage as a metaphor and in folklore. The Greek poet Hesiod 's Works and Days (lines 109–201) lists different ages of man named after metals like gold, silver, bronze and iron to account for successive ages of humanity. Ovid 's Metamorphoses contains another retelling of

7616-410: The desert also contains Edwards Air Force Base and Naval Air Weapons Station China Lake , noted for experimental aviation and weapons projects. The Mojave Desert has several ghost towns . The most significant are the silver and copper-mining town of Calico, California , and the old railroad depot of Kelso, California . Some of the other ghost towns are more modern, created when U.S. Route 66 (and

7728-467: The deserts beginning in the 18th century. Francisco Garcés , a Franciscan friar, was the first explorer of the Mojave Desert in 1776. Garcés recorded information about the original inhabitants of the deserts. Later, as American interests expanded into California, American explorers started probing the California deserts. Jedediah Smith travelled through the Mojave Desert in 1826, finally reaching

7840-434: The dominant producers of silver until around the beginning of the 18th century, particularly Peru , Bolivia , Chile , and Argentina : the last of these countries later took its name from that of the metal that composed so much of its mineral wealth. The silver trade gave way to a global network of exchange . As one historian put it, silver "went round the world and made the world go round." Much of this silver ended up in

7952-408: The electron concentration rises as more zinc is added. Increasing the electron concentration further leads to body-centred cubic (electron concentration 1.5), complex cubic (1.615), and hexagonal close-packed phases (1.75). Naturally occurring silver is composed of two stable isotopes , Ag and Ag, with Ag being slightly more abundant (51.839% natural abundance ). This almost equal abundance

8064-411: The elements in groups 10–14 (except boron and carbon ) have very complex Ag–M phase diagrams and form the most commercially important alloys; and the remaining elements on the periodic table have no consistency in their Ag–M phase diagrams. By far the most important such alloys are those with copper: most silver used for coinage and jewellery is in reality a silver–copper alloy, and the eutectic mixture

8176-529: The exceptions are the nitrate, perchlorate, and fluoride. The tetracoordinate tetrahedral aqueous ion [Ag(H 2 O) 4 ] is known, but the characteristic geometry for the Ag cation is 2-coordinate linear. For example, silver chloride dissolves readily in excess aqueous ammonia to form [Ag(NH 3 ) 2 ] ; silver salts are dissolved in photography due to the formation of the thiosulfate complex [Ag(S 2 O 3 ) 2 ] ; and cyanide extraction for silver (and gold) works by

8288-422: The filled d subshell, as such interactions (which occur in the preceding transition metals) lower electron mobility. The thermal conductivity of silver is among the highest of all materials, although the thermal conductivity of carbon (in the diamond allotrope ) and superfluid helium-4 are higher. The electrical conductivity of silver is the highest of all metals, greater even than copper. Silver also has

8400-534: The fluoride ion is so small that it has a considerable solvation energy and hence is highly water-soluble and forms di- and tetrahydrates. The other three silver halides are highly insoluble in aqueous solutions and are very commonly used in gravimetric analytical methods. All four are photosensitive (though the monofluoride is so only to ultraviolet light), especially the bromide and iodide which photodecompose to silver metal, and thus were used in traditional photography . The reaction involved is: The process

8512-523: The formation of the complex [Ag(CN) 2 ] . Silver cyanide forms the linear polymer {Ag–C≡N→Ag–C≡N→}; silver thiocyanate has a similar structure, but forms a zigzag instead because of the sp - hybridized sulfur atom. Chelating ligands are unable to form linear complexes and thus silver(I) complexes with them tend to form polymers; a few exceptions exist, such as the near-tetrahedral diphosphine and diarsine complexes [Ag(L–L) 2 ] . Under standard conditions, silver does not form simple carbonyls, due to

8624-412: The free alkene. Yellow silver carbonate , Ag 2 CO 3 can be easily prepared by reacting aqueous solutions of sodium carbonate with a deficiency of silver nitrate. Its principal use is for the production of silver powder for use in microelectronics. It is reduced with formaldehyde , producing silver free of alkali metals: Silver carbonate is also used as a reagent in organic synthesis such as

8736-573: The gold-rich side) and have a vast range of hardnesses and colours, silver–copper–zinc alloys are useful as low-melting brazing alloys, and silver–cadmium– indium (involving three adjacent elements on the periodic table) is useful in nuclear reactors because of its high thermal neutron capture cross-section , good conduction of heat, mechanical stability, and resistance to corrosion in hot water. The word silver appears in Old English in various spellings, such as seolfor and siolfor . It

8848-459: The hands of the Chinese. A Portuguese merchant in 1621 noted that silver "wanders throughout all the world... before flocking to China, where it remains as if at its natural center." Still, much of it went to Spain, allowing Spanish rulers to pursue military and political ambitions in both Europe and the Americas. "New World mines", concluded several historians, "supported the Spanish empire." In

8960-412: The highest electrical conductivity , thermal conductivity , and reflectivity of any metal . Silver is found in the Earth's crust in the pure, free elemental form (" native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite . Most silver is produced as a byproduct of copper , gold, lead , and zinc refining . Silver has long been valued as

9072-623: The homeland of the proposed Southern Uto-Aztecan group has been placed on the coast of Sonora . A contrary proposal suggests the homeland of Proto-Uto-Aztecan to have been much farther to the south; it was published in 2001 by Jane H. Hill , based on her reconstruction of maize-related vocabulary in Proto-Uto-Aztecan. By her theory, the assumed speakers of Proto-Uto-Aztecan were maize cultivators in Mesoamerica , who gradually moved north, bringing maize cultivation with them, during

9184-793: The international destination of Las Vegas. The Mojave is also known for its scenery, playing host to Death Valley National Park , Joshua Tree National Park , and the Mojave National Preserve . Lakes Mead , Mohave , and Havasu provide water sports recreation, and vast off-road areas entice off-road enthusiasts. The Mojave Desert also includes three California State Parks , the Antelope Valley California Poppy Reserve , in Lancaster , Saddleback Butte State Park , in Hi Vista and Red Rock Canyon State Park . Mojave Narrows Park , operated by San Bernardino County,

9296-470: The largest solar farms in the world, was built approximately five miles from Joshua Tree National Park . An endangered Yuma clapper rail was found dead at the site in 2014, spurring efforts from conservation groups to protect birds from the so-called lake effect, a phenomenon in which birds can mistake the reflective glare of solar panels for a body of water. The Mojave Desert is one of the most popular spots for tourism in North America, primarily because of

9408-442: The late summer months, there is also the possibility of strong thunderstorms, which bring heavy showers or cloudbursts. These storms can result in flash flooding . The Mojave Desert has not historically supported a fire regime because of low fuel loads and connectivity. However, in the last few decades, invasive annual plants such as some within the genera Bromus , Schismus and Brassica have facilitated fires by serving as

9520-509: The lesser-known U.S. Route 91 ) were abandoned in favor of the construction of Interstates . CA SR 14 , Interstate 15 , Interstate 40 , CA SR 58 , CA SR 138 , US Route 95 , and US Route 395 are the main highways that traverse the Mojave Desert. The rock that forms the Mojave Desert was likely created under shallow water in the Precambrian . Sedimentary processes left large deposits of limestones, silicates, and dolomites. During

9632-407: The lowest contact resistance of any metal. Silver is rarely used for its electrical conductivity, due to its high cost, although an exception is in radio-frequency engineering , particularly at VHF and higher frequencies where silver plating improves electrical conductivity because those currents tend to flow on the surface of conductors rather than through the interior. During World War II in

9744-618: The metal. The situation changed with the discovery of cupellation , a technique that allowed silver metal to be extracted from its ores. While slag heaps found in Asia Minor and on the islands of the Aegean Sea indicate that silver was being separated from lead as early as the 4th millennium BC , and one of the earliest silver extraction centres in Europe was Sardinia in the early Chalcolithic period , these techniques did not spread widely until later, when it spread throughout

9856-628: The most basal clade in Wheeler & Whiteley's (2014) Uto-Aztecan phylogram . A survey of agriculture-related vocabulary by Merrill (2012) found that the agricultural vocabulary can be reconstructed for only Southern Uto-Aztecan. That supports a conclusion that the Proto-Uto-Aztecan speech community did not practice agriculture but adopted it only after entering Mesoamerica from the north. A more recent proposal from 2014, by David L. Shaul, presents evidence suggesting contact between Proto-Uto-Aztecan and languages of central California, such as Esselen and

9968-434: The most important oxidation state for silver in complexes is +1. The Ag cation is diamagnetic, like its homologues Cu and Au , as all three have closed-shell electron configurations with no unpaired electrons: its complexes are colourless provided the ligands are not too easily polarized such as I . Ag forms salts with most anions, but it is reluctant to coordinate to oxygen and thus most of these salts are insoluble in water:

10080-546: The most stable being Ag with a half-life of 41.29 days, Ag with a half-life of 7.45 days, and Ag with a half-life of 3.13 hours. Silver has numerous nuclear isomers , the most stable being Ag ( t 1/2 = 418 years), Ag ( t 1/2 = 249.79 days) and Ag ( t 1/2 = 8.28 days). All of the remaining radioactive isotopes have half-lives of less than an hour, and the majority of these have half-lives of less than three minutes. Isotopes of silver range in relative atomic mass from 92.950 u ( Ag) to 129.950 u ( Ag);

10192-537: The neighboring Sonoran and Great Basin deserts. The animal species of the Mojave Desert have generally fewer endemics than its flora. However, endemic fauna of the Mojave Desert include Kelso Dunes jerusalem cricket ( Ammopelmatus kelsoensis), the Kelso Dunes shieldback katydid ( Eremopedes kelsoensis ), the Mohave ground squirrel ( Spermophilus Mohavensis ) and Amargosa vole ( Microtus californicus scirpensis ). The Mojave fringe-toed lizard ( Uma Scopari a)

10304-588: The only objects with a high-enough palladium-to-silver ratio to yield measurable variations in Ag abundance. Radiogenic Ag was first discovered in the Santa Clara meteorite in 1978. Pd– Ag correlations observed in bodies that have clearly been melted since the accretion of the Solar System must reflect the presence of unstable nuclides in the early Solar System. Silver is a rather unreactive metal. This

10416-625: The ores of copper, copper-nickel, lead, and lead-zinc obtained from Peru , Bolivia , Mexico , China , Australia , Chile , Poland and Serbia . Peru, Bolivia and Mexico have been mining silver since 1546, and are still major world producers. Top silver-producing mines are Cannington (Australia), Fresnillo (Mexico), San Cristóbal (Bolivia), Antamina (Peru), Rudna (Poland), and Penasquito (Mexico). Top near-term mine development projects through 2015 are Pascua Lama (Chile), Navidad (Argentina), Jaunicipio (Mexico), Malku Khota (Bolivia), and Hackett River (Canada). In Central Asia , Tajikistan

10528-423: The oxide.) Silver(I) oxide is very easily reduced to metallic silver, and decomposes to silver and oxygen above 160 °C. This and other silver(I) compounds may be oxidized by the strong oxidizing agent peroxodisulfate to black AgO, a mixed silver(I,III) oxide of formula Ag Ag O 2 . Some other mixed oxides with silver in non-integral oxidation states, namely Ag 2 O 3 and Ag 3 O 4 , are also known, as

10640-451: The period of roughly 4,500 to 3,000 years ago. The geographic diffusion of speakers corresponded to the breakup of linguistic unity. The hypothesis has been criticized on several grounds, and it is not generally accepted by Uto-Aztecanists. Using computational phylogenetic methods, Wheeler & Whiteley (2014) also suggest a southern homeland for Proto-Uto-Aztecan in or near the area occupied by historical Cora and some Nahua. Nahuatl forms

10752-577: The photosensitivity of silver salts, this behaviour may be induced by shining a light on its crystals. Silver complexes tend to be similar to those of its lighter homologue copper. Silver(III) complexes tend to be rare and very easily reduced to the more stable lower oxidation states, though they are slightly more stable than those of copper(III). For instance, the square planar periodate [Ag(IO 5 OH) 2 ] and tellurate [Ag{TeO 4 (OH) 2 } 2 ] complexes may be prepared by oxidising silver(I) with alkaline peroxodisulfate . The yellow diamagnetic [AgF 4 ]

10864-961: The presence of potassium bromide ( KBr ). These compounds are used in photography to bleach silver images, converting them to silver bromide that can either be fixed with thiosulfate or redeveloped to intensify the original image. Silver forms cyanide complexes ( silver cyanide ) that are soluble in water in the presence of an excess of cyanide ions. Silver cyanide solutions are used in electroplating of silver. The common oxidation states of silver are (in order of commonness): +1 (the most stable state; for example, silver nitrate , AgNO 3 ); +2 (highly oxidising; for example, silver(II) fluoride , AgF 2 ); and even very rarely +3 (extreme oxidising; for example, potassium tetrafluoroargentate(III), KAgF 4 ). The +3 state requires very strong oxidising agents to attain, such as fluorine or peroxodisulfate , and some silver(III) compounds react with atmospheric moisture and attack glass. Indeed, silver(III) fluoride

10976-406: The primary decay mode before the most abundant stable isotope, Ag, is electron capture and the primary mode after is beta decay . The primary decay products before Ag are palladium (element 46) isotopes, and the primary products after are cadmium (element 48) isotopes. The palladium isotope Pd decays by beta emission to Ag with a half-life of 6.5 million years. Iron meteorites are

11088-419: The reaction of the bis(NHC)silver(I) complex with bis(acetonitrile)palladium dichloride or chlorido(dimethyl sulfide)gold(I) : Silver forms alloys with most other elements on the periodic table. The elements from groups 1–3, except for hydrogen , lithium , and beryllium , are very miscible with silver in the condensed phase and form intermetallic compounds; those from groups 4–9 are only poorly miscible;

11200-526: The real potential to drastically affect flora and fauna of the Mojave Desert. Agricultural development along the Colorado river , close to the Eastern boundary of the Mojave Desert, also causes habitat loss and degradation. Areas that are particularly affected by human development include Ward Valley and Riverside county. The United States military also maintains installations in the Mojave Desert, making

11312-512: The region and beyond. The origins of silver production in India , China , and Japan were almost certainly equally ancient, but are not well-documented due to their great age. When the Phoenicians first came to what is now Spain , they obtained so much silver that they could not fit it all on their ships, and as a result used silver to weight their anchors instead of lead. By the time of

11424-701: The same as that of mercury . It mostly occurs in sulfide ores, especially acanthite and argentite , Ag 2 S. Argentite deposits sometimes also contain native silver when they occur in reducing environments, and when in contact with salt water they are converted to chlorargyrite (including horn silver ), AgCl, which is prevalent in Chile and New South Wales . Most other silver minerals are silver pnictides or chalcogenides ; they are generally lustrous semiconductors. Most true silver deposits, as opposed to argentiferous deposits of other metals, came from Tertiary period vulcanism. The principal sources of silver are

11536-693: The same time period. This production came to a nearly complete halt with the fall of the Roman Empire, not to resume until the time of Charlemagne : by then, tens of thousands of tonnes of silver had already been extracted. Central Europe became the centre of silver production during the Middle Ages , as the Mediterranean deposits exploited by the ancient civilisations had been exhausted. Silver mines were opened in Bohemia , Saxony , Alsace ,

11648-557: The southern Sierra Nevada mountains and Transverse Ranges in the Southwestern United States . Named for the indigenous Mohave people , it is located primarily in southeastern California and southwestern Nevada , with small portions extending into Arizona and Utah . The Mojave Desert, together with the Sonoran , Chihuahuan , and Great Basin deserts, form a larger North American Desert . Of these,

11760-422: The stability of the 4d orbitals), so that the chemistry of silver is predominantly that of the +1 oxidation state, reflecting the increasingly limited range of oxidation states along the transition series as the d-orbitals fill and stabilize. Unlike copper , for which the larger hydration energy of Cu as compared to Cu is the reason why the former is the more stable in aqueous solution and solids despite lacking

11872-445: The stable filled d-subshell of the latter, with silver this effect is swamped by its larger second ionisation energy. Hence, Ag is the stable species in aqueous solution and solids, with Ag being much less stable as it oxidizes water. Most silver compounds have significant covalent character due to the small size and high first ionization energy (730.8 kJ/mol) of silver. Furthermore, silver's Pauling electronegativity of 1.93

11984-411: The story, containing an illustration of silver's metaphorical use of signifying the second-best in a series, better than bronze but worse than gold: But when good Saturn , banish'd from above, Was driv'n to Hell, the world was under Jove . Succeeding times a silver age behold, Excelling brass, but more excell'd by gold. In folklore, silver was commonly thought to have mystic powers: for example,

12096-458: The weakness of the Ag–C bond. A few are known at very low temperatures around 6–15 K, such as the green, planar paramagnetic Ag(CO) 3 , which dimerizes at 25–30 K, probably by forming Ag–Ag bonds. Additionally, the silver carbonyl [Ag(CO)] [B(OTeF 5 ) 4 ] is known. Polymeric AgLX complexes with alkenes and alkynes are known, but their bonds are thermodynamically weaker than even those of

12208-499: The world production of silver was around a meagre 50 tonnes per year. In the Americas, high temperature silver-lead cupellation technology was developed by pre-Inca civilizations as early as AD 60–120; silver deposits in India, China, Japan, and pre-Columbian America continued to be mined during this time. With the discovery of America and the plundering of silver by the Spanish conquistadors, Central and South America became

12320-413: Was also aware of sheet silver, exemplifying the malleability and ductility of the metal: "Silver spread into plates is brought from Tarshish, and gold from Uphaz, the work of the workman, and of the hands of the founder: blue and purple is their clothing: they are all the work of cunning men." (Jeremiah 10:9) Silver also has more negative cultural meanings: the idiom thirty pieces of silver , referring to

12432-510: Was more often used ornamentally or as money. Since silver is more reactive than gold, supplies of native silver were much more limited than those of gold. For example, silver was more expensive than gold in Egypt until around the fifteenth century BC: the Egyptians are thought to have separated gold from silver by heating the metals with salt, and then reducing the silver chloride produced to

12544-457: Was the usual Proto-Indo-European word for the metal, whose reflexes are missing in Germanic and Balto-Slavic. Silver was known in prehistoric times: the three metals of group 11, copper, silver, and gold, occur in the elemental form in nature and were probably used as the first primitive forms of money as opposed to simple bartering. Unlike copper, silver did not lead to the growth of metallurgy , on account of its low structural strength; it

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