United States dollar
The United States dollar is the official currency of the United States and its territories per the United States Constitution since 1792. In practice, the dollar is divided into 100 smaller cent units, but is divided into 1000 mills for accounting; the circulating paper money consists of Federal Reserve Notes that are denominated in United States dollars. Since the suspension in 1971 of convertibility of paper U. S. currency into any precious metal, the U. S. dollar is, de facto, fiat money. As it is the most used in international transactions, the U. S. dollar is the world's primary reserve currency. Several countries use it as their official currency, in many others it is the de facto currency. Besides the United States, it is used as the sole currency in two British Overseas Territories in the Caribbean: the British Virgin Islands and Turks and Caicos Islands. A few countries use the Federal Reserve Notes for paper money, while still minting their own coins, or accept U. S. dollar coins. As of June 27, 2018, there are $1.67 trillion in circulation, of which $1.62 trillion is in Federal Reserve notes.
Article I, Section 8 of the U. S. Constitution provides that the Congress has the power "To coin money". Laws implementing this power are codified at 31 U. S. C. § 5112. Section 5112 prescribes the forms; these coins are both designated in Section 5112 as "legal tender" in payment of debts. The Sacagawea dollar is one example of the copper alloy dollar; the pure silver dollar is known as the American Silver Eagle. Section 5112 provides for the minting and issuance of other coins, which have values ranging from one cent to 100 dollars; these other coins are more described in Coins of the United States dollar. The Constitution provides that "a regular Statement and Account of the Receipts and Expenditures of all public Money shall be published from time to time"; that provision of the Constitution is made specific by Section 331 of Title 31 of the United States Code. The sums of money reported in the "Statements" are being expressed in U. S. dollars. The U. S. dollar may therefore be described as the unit of account of the United States.
The word "dollar" is one of the words in the first paragraph of Section 9 of Article I of the Constitution. There, "dollars" is a reference to the Spanish milled dollar, a coin that had a monetary value of 8 Spanish units of currency, or reales. In 1792 the U. S. Congress passed a Coinage Act. Section 9 of that act authorized the production of various coins, including "DOLLARS OR UNITS—each to be of the value of a Spanish milled dollar as the same is now current, to contain three hundred and seventy-one grains and four sixteenth parts of a grain of pure, or four hundred and sixteen grains of standard silver". Section 20 of the act provided, "That the money of account of the United States shall be expressed in dollars, or units... and that all accounts in the public offices and all proceedings in the courts of the United States shall be kept and had in conformity to this regulation". In other words, this act designated the United States dollar as the unit of currency of the United States. Unlike the Spanish milled dollar, the U.
S. dollar is based upon a decimal system of values. In addition to the dollar the coinage act established monetary units of mill or one-thousandth of a dollar, cent or one-hundredth of a dollar, dime or one-tenth of a dollar, eagle or ten dollars, with prescribed weights and composition of gold, silver, or copper for each, it was proposed in the mid-1800s that one hundred dollars be known as a union, but no union coins were struck and only patterns for the $50 half union exist. However, only cents are in everyday use as divisions of the dollar. XX9 per gallon, e.g. $3.599, more written as $3.599⁄10. When issued in circulating form, denominations equal to or less than a dollar are emitted as U. S. coins while denominations equal to or greater than a dollar are emitted as Federal Reserve notes. Both one-dollar coins and notes are produced today, although the note form is more common. In the past, "paper money" was issued in denominations less than a dollar and gold coins were issued for circulation up to the value of $20.
The term eagle was used in the Coinage Act of 1792 for the denomination of ten dollars, subsequently was used in naming gold coins. Paper currency less than one dollar in denomination, known as "fractional currency", was sometimes pejoratively referred to as "shinplasters". In 1854, James Guthrie Secretary of the Treasury, proposed creating $100, $50 and $25 gold coins, which were referred to as a "Union", "Half Union", "Quarter Union", thus implying a denomination of 1 Union = $100. Today, USD notes are made from cotton fiber paper, unlike most common paper, made of wood fiber. U. S. coins are produced by the United States Mint. U. S. dollar banknotes are printed by the Bureau of Engraving and Printing and, since 1914, have been issued by t
Fixed exchange-rate system
A fixed exchange rate, sometimes called a pegged exchange rate, is a type of exchange rate regime in which a currency's value is fixed against either the value of another single currency, a basket of other currencies, or another measure of value, such as gold. There are risks to using a fixed exchange rate. A fixed exchange rate is used to stabilize the value of a currency by directly fixing its value in a predetermined ratio to a different, more stable, or more internationally prevalent currency to which the value is pegged. In doing so, the exchange rate between the currency and its peg does not change based on market conditions, unlike flexible exchange regime; this makes trade and investments between the two currency areas easier and more predictable and is useful for small economies that borrow in foreign currency and in which external trade forms a large part of their GDP. A fixed exchange-rate system can be used to control the behavior of a currency, such as by limiting rates of inflation.
However, in doing so, the pegged currency is controlled by its reference value. As such, when the reference value rises or falls, it follows that the value of any currencies pegged to it will rise and fall in relation to other currencies and commodities with which the pegged currency can be traded. In other words, a pegged currency is dependent on its reference value to dictate how its current worth is defined at any given time. In addition, according to the Mundell–Fleming model, with perfect capital mobility, a fixed exchange rate prevents a government from using domestic monetary policy to achieve macroeconomic stability. In a fixed exchange-rate system, a country’s central bank uses an open market mechanism and is committed at all times to buy and/or sell its currency at a fixed price in order to maintain its pegged ratio and, the stable value of its currency in relation to the reference to which it is pegged. To maintain a desired exchange rate, the central bank during the devaluation of the domestic money, sells its foreign money in the reserves and buys back the domestic money.
This creates an artificial demand for the domestic money. In case of an undesired appreciation of the domestic money, the central bank buys back the foreign money and thus flushes the domestic money into the market for decreasing the demand and exchange rate; the central bank from its reserves provides the assets and/or the foreign currency or currencies which are needed in order to finance any imbalance of payments. In the 21st century, the currencies associated with large economies do not fix or peg exchange rates to other currencies; the last large economy to use a fixed exchange rate system was the People's Republic of China, which, in July 2005, adopted a more flexible exchange rate system, called a managed exchange rate. The European Exchange Rate Mechanism is used on a temporary basis to establish a final conversion rate against the euro from the local currencies of countries joining the Eurozone; the gold standard or gold exchange standard of fixed exchange rates prevailed from about 1870 to 1914, before which many countries followed bimetallism.
The period between the two world wars was transitory, with the Bretton Woods system emerging as the new fixed exchange rate regime in the aftermath of World War II. It was formed with an intent to rebuild war-ravaged nations after World War II through a series of currency stabilization programs and infrastructure loans; the early 1970's saw the breakdown of the system and its replacement by a mixture of fluctuating and fixed exchange rates. Timeline of the fixed exchange rate system: The earliest establishment of a gold standard was in the United Kingdom in 1821 followed by Australia in 1852 and Canada in 1853. Under this system, the external value of all currencies was denominated in terms of gold with central banks ready to buy and sell unlimited quantities of gold at the fixed price; each central bank maintained gold reserves as their official reserve asset. For example, during the “classical” gold standard period, the U. S. dollar was defined as 0.048 troy oz. of pure gold. Following the Second World War, the Bretton Woods system replaced gold with the U.
S. dollar as the official reserve asset. The regime intended to combine binding legal obligations with multilateral decision-making through the International Monetary Fund; the rules of this system were set forth in the articles of agreement of the IMF and the International Bank for Reconstruction and Development. The system was a monetary order intended to govern currency relations among sovereign states, with the 44 member countries required to establish a parity of their national currencies in terms of the U. S. dollar and to maintain exchange rates within 1% of parity by intervening in their foreign exchange markets. The U. S. dollar was the only currency strong enough to meet the rising demands for international currency transactions, so the United States agreed both to link the dollar to gold at the rate of $35 per ounce of gold and to convert dollars into gold at that price. Due to concerns about America's deteriorating payments situation and massive flight of liquid capital from the U.
S. President Richard Nixon suspended the convertibility of the dollar into gold on 15 August 1971. In December 1971, the Smithsonian Agreement paved the way for the increase in the value of the dollar price of gold from US$35.50 to US$38 an ounce. Speculation against the dollar in March 1973 led to the birth of the independent float, thus terminating the Bretton Woods system. Since March 1973, the floating exchange rate has been followed and formally recognize
Fahd of Saudi Arabia
Fahd bin Abdulaziz Al Saud, Custodian of the Two Holy Mosques was King of Saudi Arabia from 1982 to 2005. He was one of the fourth of his six sons who were kings. Fahd was appointed Crown Prince when his half-brother Khalid succeeded another half-brother King Faisal, assassinated in 1975. Fahd was viewed as the de facto Prime Minister during King Khalid's reign in part due to the latter's ill health. Fahd ascended to the throne on the death of King Khalid on 13 June 1982. King Fahd is credited for having introduced the Basic Law of Saudi Arabia in 1992, he suffered a debilitating stroke in 1995, after which he was unable to continue performing his full official duties. His half-brother Abdullah, the country's Crown Prince, served as de facto regent of the kingdom, succeeded Fahd as monarch upon his death in August 2005. Fahd bin Abdulaziz was born in Riyadh in 1921, he was the eighth son of Ibn Saud. His mother was Hassa Al Sudairi and he was the eldest member of the Sudairi Seven. Fahd's education took place at the Princes' School in Riyadh, a school established by Ibn Saud for the education of members of the House of Saud.
He received education for four years. While at the Princes' School, Fahd studied under tutors including Sheikh Abdul-Ghani Khayat, he went on to receive education at the Religious Knowledge Institute in Mecca. Prince Fahd was made a member of the royal advisory board at his mother's urging. In 1945, Prince Fahd traveled on his first state visit to San Francisco for the signing of the UN charter. On this trip he served under his brother Prince Faisal, at the time Saudi Arabia's foreign minister. Fahd led his first official state visit in 1953, attending the coronation of Queen Elizabeth II on behalf of the House of Saud. On 24 December 1953, Prince Fahd was appointed education minister, being the first person holding this post in the country. Prince Fahd led the Saudi delegation to the League of Arab States in 1959, signifying his increasing prominence in the House of Saud—and that he was being groomed for a more significant role. In 1962, Fahd was given the important post of interior minister; as interior minister he headed the Saudi delegation at a meeting of Arab Heads of State in Egypt in 1965.
He was named second deputy prime minister in 1967, created for the first time by King Faisal. After the death of King Faisal in 1975, Fahd was named first deputy prime minister and concurrently crown prince in 1975. Although Prince Fahd had two elder brothers, Prince Nasser and Prince Saad, who had prior claims to the throne, both were considered unsuitable candidates. By contrast, Prince Fahd had served as minister of education from 1954 to 1960 and minister of interior from 1962 to 1975. Appointment of Prince Fahd as both crown prince and first deputy prime minister made him a much more powerful figure in contrast to the status of King Khalid when he had been crown prince during King Faisal's reign; when King Khalid died on 13 June 1982, Fahd succeeded to the throne. He was the fifth king of Saudi Arabia. However, the most active period of his life was not his reign, but, he adopted the title "Custodian of the Two Holy Mosques" in 1986, replacing "His Majesty", to signify an Islamic rather than secular authority.
Fearing that the 1979 Iranian Revolution could lead to similar Islamic upheaval in Saudi Arabia, Fahd spent considerable sums, after ascending the throne in 1982, to support Saddam Hussein's Iraq in its war with Iran. In fact, according to United States Secretary of State Alexander Haig, Fahd told Haig in April 1981 that he had been used as an intermediary by President Jimmy Carter to convey an official U. S. "green light to launch the war against Iran" to Iraq, although there is considerable skepticism about this claim. Fahd was a supporter of the United Nations, he supported foreign aid and gave 5.5% of Saudi Arabia's national income through various funds the Saudi Fund for Development and the OPEC Fund for International Development. He gave aid to foreign groups such as the Bosnian Muslims in the Yugoslav Wars, as well as the Nicaraguan Contras, providing "a million dollars per month from May to December 1984". King Fahd was a strong supporter of the Palestinian cause and an opponent of the State of Israel.
Fahd was a staunch ally of the United States, has been quoted by the CIA as saying, "After Allah, we can count on the United States." He did however at times distance himself from the US, declining to allow US to use Saudi airbases to protect naval convoys after the attack on the USS Stark, in 1988 agreed to buy between fifty and sixty nuclear-payload-capable CSS-2 intermediate-range ballistic missiles. King Fahd developed a peace plan in order to resolve Arab differences between Algeria and Morocco, he actively contributed to the Taif accord in 1989 that ended conflict in Lebanon. In addition, he led the Arab world against the invasion of Kuwait by Iraq, he developed a special bond with both Syrian President Hafez Assad and Egyptian President Hosni Mobarak during his reign. He took steps to support the conservative Saudi religious establishment, including spending millions of dollars on religious education, strengthened separation of the sexes and power of the religious police, publicly endorsed Sheikh Abd al-Aziz ibn Baz's warning to young Saudis to avoid the path of evil by not travelling to Europe and the United States.
This further distanced him from his inconvenient past. In 1990, Iraqi forces under Saddam Hussein invaded Kuwait, placing the Iraqi army on the Saudi-Kuwaiti border. King Fahd ag
Mecca spelled Makkah, is a city in the Hejazi region of the Arabian Peninsula, the plain of Tihamah in Saudi Arabia, is the capital and administrative headquarters of the Makkah Region. The city is located 70 km inland from Jeddah in a narrow valley at a height of 277 m above sea level, 340 kilometres south of Medina, its resident population in 2012 was 2 million, although visitors more than triple this number every year during the Ḥajj period held in the twelfth Muslim lunar month of Dhūl-Ḥijjah. As the birthplace of Muḥammad, the site of Muhammad's first revelation of the Quran, Mecca is regarded as the holiest city in the religion of Islam and a pilgrimage to it known as the Hajj is obligatory for all able Muslims. Mecca is home to the Kaaba, by majority description Islam's holiest site, as well as being the direction of Muslim prayer. Mecca was long ruled by Muhammad's descendants, the sharifs, acting either as independent rulers or as vassals to larger polities, it was conquered by Ibn Saud in 1925.
In its modern period, Mecca has seen tremendous expansion in size and infrastructure, home to structures such as the Abraj Al Bait known as the Makkah Royal Clock Tower Hotel, the world's fourth tallest building and the building with the third largest amount of floor area. During this expansion, Mecca has lost some historical structures and archaeological sites, such as the Ajyad Fortress. Today, more than 15 million Muslims visit Mecca annually, including several million during the few days of the Hajj; as a result, Mecca has become one of the most cosmopolitan cities in the Muslim world, although non-Muslims are prohibited from entering the city. "Mecca" is the familiar form of the English transliteration for the Arabic name of the city, although the official transliteration used by the Saudi government is Makkah, closer to the Arabic pronunciation. The word "Mecca" in English has come to be used to refer to any place that draws large numbers of people, because of this some English speaking Muslims have come to regard the use of this spelling for the city as offensive.
The Saudi government adopted Makkah as the official spelling in the 1980s, but is not universally known or used worldwide. The full official name is Makkah al-Mukarramah or Makkatu l-Mukarramah, which means "Mecca the Honored", but is loosely translated as "The Holy City of Mecca"; the ancient or early name for the site of Mecca is Bakkah. An Arabic language word, its etymology, like that of Mecca, is obscure. Believed to be a synonym for Mecca, it is said to be more the early name for the valley located therein, while Muslim scholars use it to refer to the sacred area of the city that surrounds and includes the Ka‘bah; this form is used for the name Mecca in the Quran in 3:96, while the form Mecca is used in 48:24. In South Arabic, the language in use in the southern portion of the Arabian Peninsula at the time of Muhammad, the b and m were interchangeable. Other references to Mecca in the Quran call it Umm al-Qurā, meaning "Mother of All Settlements"/"mother of villages". Another name of Mecca is Ṫihāmah.
Another name for Mecca, or the wilderness and mountains surrounding it, according to Arab and Islamic tradition, is Faran or Pharan, referring to the Desert of Paran mentioned in the Old Testament at Genesis 21:21. Arab and Islamic tradition holds that the wilderness of Paran, broadly speaking, is the Tihamah and the site where Ishmael settled was Mecca. Yaqut al-Hamawi, the 12th century Syrian geographer, wrote that Fārān was "an arabized Hebrew word, one of the names of Mecca mentioned in the Torah." Mecca is governed by the Municipality of Mecca, a municipal council of fourteen locally elected members headed by a mayor appointed by the Saudi government. As of May 2015, the mayor of the city was Dr. Osama bin Fadhel Al-Bar. Mecca is the capital of the Makkah Region; the provincial governor was prince Abdul Majeed bin Abdulaziz Al Saud from 2000 until his death in 2007. On 16 May 2007, prince Khalid bin Faisal Al Saud was appointed as the new governor; the early history of Mecca is still disputed, as there are no unambiguous references to it in ancient literature prior to the rise of Islam.
The Roman Empire took control of part of the Hejaz in 106 CE, ruling cities such as Hegra, located to the north of Mecca. Though detailed descriptions were established of Western Arabia by Rome, such as by Procopius, there are no references of a pilgrimage and trading outpost such as Mecca; the first direct mention of Mecca in external literature occurs in 741 CE, in the Byzantine-Arab Chronicle, though here the author places it in Mesopotamia rather than the Hejaz. Given the inhospitable environment and lack of historical references in Roman and Indian sources, historians including Patricia Crone and Tom Holland have cast doubt on the claim that Mecca was a major historical trading outpost; the Greek historian Diodorus Siculus writes about Arabia in his work Bibliotheca historica, describing a holy shrine: "And a temple has been set up there, holy and exceedingly revered by all Arabians". Claims have been made. However, the geographic location Diodorus describes is located in northwest Arabia, around the area of Leuke Kome, closer to Petra and within the form
A currency union involves two or more states sharing the same currency without them having any further integration. Three types of currency unions exist: Informal – unilateral adoption of foreign currency Formal – adoption of foreign currency by virtue of bilateral or multilateral agreement with the issuing authority, sometimes supplemented by issue of local currency in currency peg regime Formal with common policy – establishment by multiple countries of a common monetary policy and issuing authority for their common currencyThe theory of the optimal currency area addresses the question of how to determine what geographical regions should share a currency in order to maximize economic efficiency. Note: Every customs and monetary union and economic and monetary union has a currency union. Zimbabwe is theoretically in a currency union with four blocs as the South African rand, Botswana pula, British pound and US dollar circulate, the US Dollar was until 2016 official tender.. Additionally the autonomous and dependent territories, such as some of the EU member state special territories, are sometimes treated as separate customs territory from their mainland state or have varying arrangements of formal or de facto customs union, common market and currency union with the mainland and in regards to third countries through the trade pacts signed by the mainland state.
Between Bahrain and Abu Dhabi using the Bahraini dinar between Bahrain, Oman and the Trucial States, using the Gulf rupee from 1959 until 1966 between Aden and South Arabia, Kenya, Oman, British Somaliland, the Trucial States, Uganda and British India using the Indian rupee between Belgium and the Grand-Duchy of Luxemburg using the Belgian/Luxembourgish franc from 1921 to the Euro between British India and the Straits Settlements using the Indian rupee between Czech Republic and Slovakia using the Czechoslovak koruna between Ethiopia and Eritrea using the Ethiopian birr between France and Andorra using the French franc between the Eastern Caribbean, Barbados and Tobago and British Guiana using the British West Indies dollar between the Eastern Caribbean, Barbados and Tobago and British Guiana using the Eastern Caribbean dollar between Italy, Vatican City, San Marino using the Italian lira between Jamaica and the Cayman Islands using the Jamaican pound and Jamaican dollar between Kenya and Zanzibar using the East African rupee between Kenya and Zanzibar using the East African florin between Kenya and Zanzibar, South Arabia, British Somaliland and Italian Somaliland using the East African shilling Latin Monetary Union between France, Belgium and Switzerland, involving Greece, Romania and other countries.
Between Liberia and the United States using the United States dollar between Mauritius and Seychelles using the Mauritian rupee between Nigeria, the Gambia, Sierra Leone, the Gold Coast and Liberia using the British West African pound between Prussia and the North German states using the North German thaler between Russia and the former Soviet republics using the Soviet ruble between Qatar and all the emirates of the UAE, except Abu Dhabi using the Qatari and Dubai riyal between Saudi Arabia and Qatar using the Saudi riyal between Samoa and New Zealand using the New Zealand pound Scandinavian Monetary Union, between Denmark and Sweden between the Solomon Islands, Papua New Guinea and Australia using the Australian dollar South German guilder between Spain and Andorra using the Spanish peseta between Trinidad and Tobago and Grenada using the Trinidad and Tobago dollar between Brunei and Singapore using the Malaya and British Borneo dollar between Cambodia and Vietnam using the French Indochinese piastre between South Africa and Botswana using the South African rand between Egypt and Sudan using the Egyptian pound – until 1956 between West Germany and East Germany between 1 July 1990 and 3 October 1990, as part of a temporary, so-called "Monetary and Social Union" prior to German reunification.
Between what became the Republic of Ireland and the United Kingdom, between 1928 and 1979. The Irish Pound was held at the same value as Sterling for this period, although it was not accepted for payments in the UK. proposed pan-American monetary union – abandoned in the form proposed by Argentina proposed monetary union between the United Kingdom and Norway using the pound sterling during the late 1940s and early 1950s proposed gold-backed, pan-African monetary union put forward by Muammar Gaddafi prior to his death List of pegged currencies North American Currency Union Acocella, N. and Di Bartolomeo, G. and Tirelli, P. ‘Monetary conservatism and fiscal coordination in a monetary union’, in: ‘Economics Letters’, 94: 56-63. Bergin, Paul. "Monetary Union". In David R. Henderson. Concise Encyclopedia of Economics. Indianapolis: Library of Economics and Liberty. ISBN 978-0865976658. OCLC 237794267. CS1 maint: Extra text: editors list West Africa opts for currency union Economist- Antipodean currencies Reasons for the collapse of the Rouble Zone OECD Development Centre – the Rand Zone
Rub' al Khali
The Rub' al Khali desert is the largest contiguous sand desert in the world, encompassing most of the southern third of the Arabian Peninsula. The desert covers some 650,000 km2 including parts of Saudi Arabia, the United Arab Emirates, Yemen, it is part of the larger Arabian Desert. The desert is 1,000 kilometres long, 500 kilometres wide, its surface elevation varies from 800 metres in the southwest to around sea level in the northeast. The terrain is covered with sand dunes with heights up to 250 metres, interspersed with gravel and gypsum plains; the sand is of a reddish-orange color due to the presence of feldspar. There are brackish salt flats in some areas, such as the Umm al Samim area on the desert's eastern edge. Ali Al-Naimi reports, he goes on to say, Sand blows off the surface, of course, but the essential shape of the dunes remains intact due to the moisture leaching up into the base of the dunes from the surrounding sabkhas. Along the middle length of the desert there are a number of raised, hardened areas of calcium carbonate, marl, or clay that were once the site of shallow lakes.
These lakes existed during periods from 3,000 to 2,000 years ago. The lakes are thought to have formed as a result of "cataclysmic rainfall" similar to present-day monsoon rains and most lasted for only a few years. However, lakes in the Mundafen area in the southwest of the Rub' al Khali show evidence of lasting longer, up to 800 years, due to increased runoff from the Tuwaiq Escarpment. Evidence suggests that the lakes were home to a variety of fauna. Fossil remains indicate the presence of several animal species, such as hippopotamus, water buffalo, long-horned cattle; the lakes contained small snails and when conditions were suitable, freshwater clams. Deposits of calcium carbonate and opal phytoliths indicate the presence of plants and algae. There is evidence of human activity dating from 3,000 to 2,000 years ago, including chipped flint tools, but no actual human remains have been found; the region is classified as "hyper-arid", with annual precipitation less than 35 millimetres, daily mean relative humidity of about 52% in January and 15% in June-July.
Daily maximum temperatures average 47 °C in July and August, reaching peaks of 51 °C. The daily minimum average is 12 °C in February, although frosts have been recorded. Daily extremes of temperature are considerable. Fauna includes rodents, while plants live throughout the Empty Quarter; as an ecoregion, the Rub' al Khali falls within the Arabian Desert and East Saharo-Arabian xeric shrublands. The Asiatic cheetahs, once widespread in Saudi Arabia, are regionally extinct from the desert. Shaybah oil field was discovered in 1968. South Ghawar, the largest oil field in the world, extends southward into the northernmost parts of the Empty Quarter. Desertification has increased through recent millennia. Before desertification made the caravan trails leading across the Rub' al Khali so difficult, the caravans of the frankincense trade crossed now impassable stretches of wasteland, until about CE 300, it has been suggested that a lost city, region or people, depended on such trade. The archaeological remains include a fortification/administration building and bases of circular pillars.
The traces of camel tracks, unidentifiable on the ground, appear in satellite images. Today the inhabitants of the Empty Quarter are members of various local tribes – for example, the Al Murrah tribe has the largest area based between Al-Ahsa and Najran; the Banu Yam and Banu Hamdan, the Bani Yas. A few road links connect these tribal settlements to the area's water resources and oil production centers; the first documented journeys by non-resident explorers were made by British explorers Bertram Thomas and St. John Philby in the early 1930s. Between 1946 and 1950, Wilfred Thesiger crossed the area several times and mapped large parts of the Empty Quarter including the mountains of Oman, as described in his 1959 book Arabian Sands. In June 1950, a US Air Force expedition crossed the Rub' al Khali from Dhahran, Saudi Arabia, to central Yemen and back in trucks to collect specimens for the Smithsonian Institution and to test desert survival procedures. In 1999, Jamie Clarke became the first Westerner to cross the Empty Quarter of Arabia in fifty years.
His team of six, including three Bedouin, spent 40 days crossing the desert with a caravan of 13 camels. On 25 February 2006, a scientific excursion organized by the Saudi Geological Survey began to explore the Empty Quarter; the expedition consisted of 89 environmentalists and scientists from Saudi Arabia and abroad. Various types of fossilized creatures as well as meteorites were discovered in the desert; the expedition discovered 31 new plant species and plant varieties, as well as 24 species of birds that inhabit the region, which fascinated scientists as to how they have survived under the harsh conditions of the Empty Quarter. In 2012, Alastair Humphreys and Leon McCarron pulled a specially designed cart from Salalah to Dubai, they produced a documentary film about their journey and how it compared to those of Wilfred Thesiger. On 4 February 2013, a South African team including Alex Harris, Marco Broccardo, David Joyce claimed that they became the first people to cross the border close to Oman of the Empty Quarter unsupported and on foot, in a journey whi
The fineness of a precious metal object represents the weight of fine metal therein, in proportion to the total weight which includes alloying base metals and any impurities. Alloy metals are added to increase hardness and durability of coins and jewelry, alter colors, decrease the cost per weight, or avoid the cost of high-purity refinement. For example, copper is added to the precious metal silver to make a more durable alloy for use in coins and jewelry. Coin silver, used for making silver coins in the past, contains 90% silver and 10% copper, by mass. Sterling silver contains 92.5% silver and 7.5% of other metals copper, by mass. Various ways of expressing fineness have been used and two remain in common use: millesimal fineness expressed in units of parts per 1,000 and karats used only for gold. Karats measure the parts per 24, so that 18 karat = 18⁄24 = 75% and 24 karat gold is considered 100% gold. Millesimal fineness is a system of denoting the purity of platinum and silver alloys by parts per thousand of pure metal by mass in the alloy.
For example, an alloy containing 75% gold is denoted as "750". Many European countries use decimal hallmark stamps rather than "14K", "18K", etc., used in the United Kingdom and United States. It is an extension of the older karat system of denoting the purity of gold by fractions of 24, such as "18 karat" for an alloy with 75% pure gold by mass; the millesimal fineness is rounded to a three figure number where used as a hallmark, the fineness may vary from the traditional versions of purity. Here are the most common millesimal finenesses used for precious metals and the most common terms associated with them. 999.5: what most dealers would buy as if 100% pure. Refined by the Perth Mint in 1957. 999.99—five nines fine: the purest type of gold produced. 999.9—four nines fine: e.g. ordinary Canadian Gold Maple Leaf and American Buffalo coins 999—24 karat occasionally known as three nines fine: e.g. Chinese Gold Panda coins 995: the minimum allowed in Good Delivery gold bars 990—two nines fine 986—Ducat fineness: used by Venetian and Holy Roman Empire mints.
This was achieved by the Royal Silver Company of Bolivia. 999.9—four nines fine: ultra-fine silver used by the Royal Canadian Mint for their Silver Maple Leaf and other silver coins 999—fine silver or three nines fine: used in Good Delivery bullion bars and most current silver bullion coins 980: common standard used in Mexico ca. 1930–45 958: Britannia silver 950: French 1st Standard 935: Swiss standard for watchcases after 1887, to meet the British Merchandise Marks Act and to be of equal grade to 925 Sterling. Sometimes claimed to have arisen as a Swiss misunderstanding of the standard required for British Sterling. Marked with three Swiss bears. 925: Sterling silver equivalent to "plata de primera ley" in Spain 917: a standard used for the minting of Indian silver, during the British raj 900: one nine fine, coin-silver, or 90% silver: e.g. Flowing Hair and 1837–1964 U. S. silver coins 892.4: US coinage 1485⁄1664 fine "standard silver" as defined by the Coinage Act of 1792: e.g. Draped Bust and Capped Bust U.
S. silver coins 875: Swiss standard used for export watchcases. 835: a standard predominantly used in Germany after 1884, for the minting of coins in countries of the Latin Monetary Union 833: a common standard for continental silver among the Dutch and Germans 830: a common standard used in older Scandinavian silver 800: the minimum standard for silver in Germany after 1884. The karat system is a standard adopted by US federal law. K is the karat rating of the material, Mg is the mass of pure gold in the alloy, Mm is the total mass of the material.24-karat gold is pure, 18-karat gold is 18 parts gold, 6 parts another metal, 12-karat gold is 12 parts gold, so forth. In England, the karat was divisible into four grains, the grain was divisible into four quarts. For example, a gold alloy of 127⁄128 fineness could have been described as being 23-karat, 3-grain, 1-quart gold; the karat fractional system is being complemented or superseded by the millesimal system, descr