Aristotle described two types of political revolution, Complete change from one constitution to another Modification of an existing constitution. Revolutions have occurred through history and vary widely in terms of methods, duration. Their results include major changes in culture and socio-political institutions, scholarly debates about what does and does not constitute a revolution center on several issues. Several generations of scholarly thought on revolutions have generated many competing theories, the word revolucion is known in French from the 13th century, and revolution in English by the late fourteenth century, with regards to the revolving motion of celestial bodies. Revolution in the sense of representing abrupt change in an order is attested by at least 1450. Political usage of the term had been established by 1688 in the description of the replacement of James II with William III. The process was termed The Glorious Revolution, there are many different typologies of revolutions in social science and literature.
One of several different Marxist typologies divides revolutions into pre-capitalist, early bourgeois, bourgeois-democratic, early proletarian, Charles Tilly, a modern scholar of revolutions, differentiated between a coup, a top-down seizure of power, a civil war, a revolt and a great revolution. Other types of revolution, created for other typologies, include the social revolutions, proletarian or communist revolutions, failed or abortive revolutions, the term revolution has been used to denote great changes outside the political sphere. Such revolutions are usually recognized as having transformed in society, culture and technology much more than political systems, some can be global, while others are limited to single countries. One of the examples of the usage of the word revolution in such context is the Industrial Revolution. Note that such revolutions fit the slow revolution definition of Tocqueville, a similar example is the Digital Revolution. Perhaps most often, the revolution is employed to denote a change in socio-political institutions.
Jeff Goodwin gives two definitions of a revolution and socioeconomic revolutions have been studied in many social sciences, particularly sociology, political sciences and history. Scholars of revolutions, like Jack Goldstone, differentiate four current generations of scholarly research dealing with revolutions, the scholars of the first generation such as Gustave Le Bon, Charles A. Second generation theorists sought to develop detailed theories of why and when revolutions arise and they can be divided into three major approaches, psychological and political. The works of Ted Robert Gurr, Ivo K. Feierbrand, Rosalind L. Feierbrand, James A. Geschwender, David C. Schwartz, the second group, composed of academics such as Chalmers Johnson, Neil Smelser, Bob Jessop, Mark Hart, Edward A. As in the school, they differed in their definitions of what causes disequilibrium
It is a tehsil of Hyderabad district, India. The region is known for the mines that have produced some of the worlds most famous gems, including the Koh-i-Noor, the Hope Diamond and the Nassak Diamond. Golkonda was originally known as Mankal. Golkonda Fort was first built by the Kakatiya dynasty as part of their defenses along the lines of the Kondapalli Fort. The city and the fortress were built on a hill that is 120 meters high. The fort was rebuilt and strengthened by Rani Rudrama Devi and her successor Prataparudra, the fort came under the control of the Musunuri Nayaks, who defeated the Tughlaqi army occupying Warangal. It was ceded by the Musunuri Kapaya Nayak to the Bahmani Sultanate as part of a treaty in 1364, under the Bahmani Sultanate, Golkonda slowly rose to prominence. Sultan Quli Qutb-ul-Mulk, sent as a governor of Telangana, established it as the seat of his government around 1501, Bahmani rule gradually weakened during this period, and Sultan Quli formally became independent in 1538, establishing the Qutb Shahi dynasty based in Golkonda.
Over a period of 62 years, the mud fort was expanded by the first three Qutb Shahi sultans into the present structure, a fortification of granite extending around 5 km in circumference. It remained the capital of the Qutb Shahi dynasty until 1590 when the capital was shifted to Hyderabad, the Qutb Shahis expanded the fort, whose 7 kilometres outer wall enclosed the city. The fort finally fell into ruin in 1687, after a long siege leading to its fall at the hands of the Mughal emperor Aurangzeb. The Golkonda Fort used to have a vault where once the famous Koh-i-Noor, Golkonda is renowned for the diamonds found on the south-east at Kollur Mine near Kollur, Guntur district and Atkur in Krishna district and cut in the city during the Kakatiya reign. At that time, India had the only known diamond mines in the world, Golkonda was the market city of the diamond trade, and gems sold there came from a number of mines. The fortress-city within the walls was famous for diamond trade, Europeans believed that diamonds were found only in the fabled Golkonda mines.
Its name has taken a generic meaning and has come to be associated with great wealth, gemologists use this classification to denote a diamond with a complete lack of nitrogen, Golconda material is referred to as 2A. During the Renaissance and the modern eras, the name Golkonda acquired a legendary aura. The lowest of these is the outermost enclosure into which we enter by the Fateh Darwaza studded with giant iron spikes near the south-eastern corner, at Fateh Darwaza can be experienced a fantastic acoustic effect, characteristic of the engineering marvels at Golkonda. A hand clap at a point below the dome at the entrance reverberates and can be heard clearly at the Bala Hisar pavilion. This worked as a note to the royals in case of an attack
The Dutch guilder or fl. was the currency of the Netherlands from the 17th century until 2002, when it was replaced by the euro. Between 1999 and 2002, the guilder was officially a national subunit of the euro, physical payments could only be made in guilder, as no euro coins or banknotes were available. The Netherlands Antillean guilder is still in use in Curaçao and Sint Maarten, in 2004, the Surinamese guilder was replaced by the Surinamese dollar. The Dutch name gulden was a Middle Dutch adjective meaning golden, the symbol ƒ or fl. for the Dutch guilder was derived from another old currency, the florin, called the florin in English. The exact exchange rate, still relevant for old contracts and for exchange of the old currency for euros at the bank, is 2.20371 Dutch guilders for 1 euro. Inverted, this gives EUR0.453780 for NLG1, before the introduction of the first guilder, there were regional and foreign golden coins that were likely referred to as gulden in Dutch. The first internationally accepted Dutch coin called gulden dates from 1517, even before that, the County of Holland had minted golden coins since 1378.
An early guilder, a 10. 61-gram.910 silver coin, was minted by the States of Holland and this guilder was divided into 20 stuivers, each of 8 duiten or 16 penningen. The guilder gradually replaced other silver coin circulating in the United Netherlands, the florijn, the daalder, the rijksdaalder, the silver ducat. Between 1810 and 1814, the Netherlands was annexed to France, after the Napoleonic wars, the Kingdom of the Netherlands readopted the guilder. In 1817 it became decimalised, with one guilder equal to 100 cents, until 1948, the plural of cent used on coins was centen, after that it was cent. The Netherlands was initially on a standard, with the guilder equal to 605.61 milligrams of fine gold or 9.615 grams of fine silver. In 1840, the standard was adjusted to 9.45 grams. In 1875, the Netherlands adopted a standard with 1 guilder equal to 604.8 milligrams of fine gold. The gold standard was suspended between 1914 and 1925 and was abandoned in 1936, following the German occupation, on 10 May 1940, the guilder was pegged to the Reichsmark at a rate of 1 guilder =1.5 Reichsmark.
This rate was reduced to 1.327 on 17 July of the same year, the liberating Allied forces set an exchange rate of 2.652 guilders =1 U. S. dollar, which became the peg for the guilder within the Bretton Woods system. In 1949, the peg was changed to 3.8 guilders =1 dollar, in 1961, the guilder was revalued to 3.62 guilders =1 dollar, a change approximately in line with that of the German mark. After 1967 guilders were made from nickel instead of silver, in 2002, the guilder was replaced by the euro at an exchange rate of 2.20371 guilders =1 Euro
It is the best known of the kremlins and includes five palaces, four cathedrals, and the enclosing Kremlin Wall with Kremlin towers. Also within this complex is the Grand Kremlin Palace, the complex serves as the official residence of the President of the Russian Federation. It had previously used to refer to the government of the Soviet Union. Kremlinology refers to the study of Soviet and Russian politics, the site has been continuously inhabited by Finno-Ugric peoples since the 2nd century BC. Vyatichi built a structure on the hill where the Neglinnaya River flowed into the Moskva River. Up to the 14th century, the site was known as the grad of Moscow, the word Kremlin was first recorded in 1331. The grad was greatly extended by Prince Yuri Dolgorukiy in 1156, destroyed by the Mongols in 1237, dmitri Donskoi replaced the oak walls with a strong citadel of white limestone in 1366–1368 on the basic foundations of the current walls, this fortification withstood a siege by Khan Tokhtamysh. Dmitris son Vasily I resumed construction of churches and cloisters in the Kremlin, the newly built Annunciation Cathedral was painted by Theophanes the Greek, Andrei Rublev, and Prokhor in 1406.
The Chudov Monastery was founded by Dmitris tutor, Metropolitan Alexis, while his widow, Eudoxia and it was during his reign that three extant cathedrals of the Kremlin, the Deposition Church, and the Palace of Facets were constructed. The highest building of the city and Muscovite Russia was the Ivan the Great Bell Tower, built in 1505–08, the Kremlin walls as they now appear were built between 1485 and 1495. Spasskie gates of the wall bear a dedication in Latin praising Petrus Antonius Solarius for the design. After construction of the new walls and churches was complete. The Kremlin was separated from the merchant town by a 30-meter-wide moat. The same tsar renovated some of his grandfathers palaces, added a new palace and cathedral for his sons, and endowed the Trinity metochion inside the Kremlin. The metochion was administrated by the Trinity Monastery and boasted the graceful tower church of St. Sergius, during the Time of Troubles, the Kremlin was held by the Polish forces for two years, between 21 September 1610 and 26 October 1612.
The Kremlins liberation by the army of prince Dmitry Pozharsky. During his reign and that of his son Alexis, the eleven-domed Upper Saviour Cathedral, Armorial Gate, Terem Palace, Amusement Palace, following the death of Alexis, the Kremlin witnessed the Moscow Uprising of 1682, from which czar Peter barely escaped. As a result, both of them disliked the Kremlin, three decades later, Peter abandoned the residence of his forefathers for his new capital, Saint Petersburg
A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut does not refer to shape, but the symmetry, the cut of a diamond greatly affects a diamonds brilliance, this means if it is cut poorly, it will be less luminous. In order to best use a diamond gemstones material properties, a number of different diamond cuts have been developed, a diamond cut constitutes a more or less symmetrical arrangement of facets, which together modify the shape and appearance of a diamond crystal. Diamond cutters must consider several factors, such as the shape and size of the crystal, the practical history of diamond cuts can be traced back to the Middle Ages, while their theoretical basis was not developed until the turn of the 20th century. The most popular of diamond cuts is the round brilliant, whose facet arrangements. Also popular are the cuts, which come in a variety of shapes—many of which were derived from the round brilliant. A diamonds cut is evaluated by trained graders, with higher grades given to stones whose symmetry, the strictest standards are applied to the round brilliant, although its facet count is invariable, its proportions are not.
Different countries base their cut grading on different ideals, one may speak of the American Standard or the Scandinavian Standard, to give but two examples. The history of diamond cuts can be traced to the late Middle Ages and this was called the point cut and dates from the mid 14th century, by 1375 there was a guild of diamond polishers at Nürnberg. By the mid 15th century, the point cut began to be improved upon, the importance of a culet was realised, and some table-cut stones may possess one. The addition of four corner facets created the old single cut, neither of these early cuts would reveal what diamond is prized for today, its strong dispersion or fire. At the time, diamond was valued chiefly for its lustre and superlative hardness. For this reason, colored gemstones such as ruby and sapphire were far more popular in jewelry of the era. In or around 1476, Lodewyk van Berquem, a Flemish polisher of Bruges, introduced the technique of absolute symmetry in the disposition of facets using a device of his own invention, the scaif.
He cut stones in the known as pendeloque or briolette. However, Indian rose cuts were far less symmetrical as their cutters had the primary interest of conserving carat weight, in either event, the rose cut continued to evolve, with its depth and arrangements of facets being tweaked. The first brilliant cuts were introduced in the middle of the 17th century, known as Mazarins, they had 17 facets on the crown. They are called double-cut brilliants as they are seen as a step up from old single cuts, yet Peruzzi-cut diamonds, when seen nowadays, seem exceedingly dull compared to modern-cut brilliants
Diamond Fund is a unique collection of gems and natural nuggets and exhibited in Moscow Kremlin, Russia. The Fund dates back to the Russian Crown treasury instituted by emperor Peter I of Russia in 1719, peters gem collection, established in 1719, was stored in the Diamond Chamber in the Winter Palace. All succeeding monarchs added their contributions to the Chamber, a 1922 study by Alexander Fersman identified 85% of all exhibits to 1719–1855, preservation and looting of imperial treasures after the Russian Revolution of 1917 is a matter of controversy and speculation. The Imperial collection was moved from Saint Petersburg to Moscow during World War I, the treasure was first exhibited to the public in November 1967. Originally a short-term show, in 1968 it became a permanent exhibition, the Russian State retains the monopoly for mining and distribution of gemstones, as set by the 1998 law On precious metals and precious stones. Diamond Fund operations are regulated by the 1999 presidential decree, for Russians it is accessible only through guided tours of fixed duration.
Foreign visitors can buy a ticket in the lobby and go on themselves. Tours in Russian only are organized daily, 10AM-2PM and 3-5PM at twenty minutes interval
The Carnatic Wars were a series of military conflicts in the middle of the 18th century in India. They were mainly fought on the territories in India which were dominated by the Nizam of Hyderabad up to the Godavari delta, as a result of these military contests, the British East India Company established its dominance among the European trading companies within India. The French company was pushed to a corner and was confined primarily to Pondichéry, the East India companys dominance eventually led to control by the British Company over most of India and eventually to the establishment of the British Raj. In the 18th century, the coastal Carnatic region was a dependency of Hyderabad, three Carnatic Wars were fought between 1746 and 1763. The Mughal Emperor Aurangzeb died in 1707 and he was succeeded by Bahadur Shah I, but there was a general decline in central control over the empire during the tenure of Jahandar Shah and emperors. Nizam-ul-Mulk established Hyderabad as an independent kingdom, a power struggle ensued after his death between his son, Nasir Jung, and his grandson, Muzaffar Jung, which was the opportunity France and England needed to interfere in Indian politics.
France aided Muzaffar Jung while England aided Nasir Jung, several erstwhile Mughal territories were autonomous such as the Carnatic, ruled by Nawab Dost Ali Khan, despite being under the legal purview of the Nizam of Hyderabad. French and English interference included those of the affairs of the Nawab, Dost Alis death sparked a power struggle between his son-in-law Chanda Sahib, supported by the French, and Muhammad Ali, supported by the English. One major instigator of the Carnatic Wars was the Frenchman Joseph François Dupleix, Dupleix sought to expand French influence in India, which was limited to a few trading outposts, the chief one being Pondicherry on the Coromandel Coast. Immediately upon his arrival in India, he organized Indian recruits under French officers for the first time, however, he was met by the equally challenging and determined young officer from the British Army, Robert Clive. The Austrian War of Succession in 1740 and the war in 1756 automatically led to a conflict in India.
in 1740 the War of the Austrian Succession broke out in Europe. Great Britain was only drawn into the war in 1744, when it entered the war opposed to France, the trading companies of both countries maintained cordial relations among themselves in India while their parent countries were bitter enemies on the European continent. Dodwell writes, Such were the relations between the English and the French that the French sent their goods and merchandise from Pondicherry to Madras for safe custody. Although French company officials were ordered to avoid conflict, British officials were not, after the British initially captured a few French merchant ships, the French called for backup from as far afield as Isle de France, beginning an escalation in naval forces in the area. In July 1746 French commander La Bourdonnais and British Admiral Edward Peyton fought an action off Negapatam. On 21 September 1746, the French captured the British outpost at Madras, La Bourdonnais had promised to return Madras to the English, but Dupleix withdrew that promise, and one to give Madras to Anwar-ud-din after the capture.
The Nawab sent a 10, 000-man army to take Madras from the French, the French made several attempts to capture the British Fort St. David at Cuddalore, but the timely arrivals of reinforcements halted these, and eventually turned the tables on the French. British Admiral Edward Boscawen besieged Pondicherry in the months of 1748
Marble Palace is one of the first Neoclassical palaces in Saint Petersburg, Russia. It is situated between the Field of Mars and Palace Quay, slightly to the east from New Michael Palace, the palace was built by Count Grigory Orlov, the favorite of Empress Catherine the Great and the most powerful Russian nobleman of the 1760s. Construction started in 1768 to designs by Antonio Rinaldi, who previously had helped decorate the palace at Caserta near Naples. The combination of sumptuous ornamentation with rigorously classicizing monumentality, as practiced by Rinaldi, the palace takes its name from its opulent decoration in a wide variety of polychrome marbles. A rough-grained Finnish granite on the floor is in subtle contrast to polished pink Karelian marble of the pilasters and white Urals marble of capitals. Panels of veined bluish gray Urals marble separate the floors, while Tallinn dolomite was employed for ornamental urns, in all,32 disparate shades of marble were used to decorate the palace.
The plan of the edifice is trapezoidal, each of its four facades, one of the facades conceals a recessed courtyard, where an armored car employed by Lenin during the October Revolution used to be mounted on display between 1937 and 1992. In 1797–1798 the structure was leased to Stanisław II Augustus, the last king of Poland, thereafter the palace belonged to Grand Duke Constantine Pavlovich and his heirs from the Konstantinovichi branch of the Romanov family. In 1843, Grand Duke Constantine Nikolayevich decided to redecorate the edifice, renaming it Constantine Palace, an adjacent church and other outbuildings were completely rebuilt, while the interior of the palace was refurbished in keeping with the eclectic tastes of its new owner. Only the main staircase and the Marble Hall survived that refacing and still retain the refined stucco work, ukhnalev A. E. Mramornyi dvorets v Sankt-Peterburge. Media related to Marble Palace at Wikimedia Commons Marble Palace Marble Palace by Saint-Petersburg. com
Amsterdam is the capital and most populous municipality of the Kingdom of the Netherlands. Its status as the capital is mandated by the Constitution of the Netherlands, although it is not the seat of the government, which is The Hague. Amsterdam has a population of 851,373 within the city proper,1,351,587 in the urban area, the city is located in the province of North Holland in the west of the country. The metropolitan area comprises much of the part of the Randstad, one of the larger conurbations in Europe. Amsterdams name derives from Amstelredamme, indicative of the citys origin around a dam in the river Amstel, during that time, the city was the leading centre for finance and diamonds. In the 19th and 20th centuries the city expanded, and many new neighborhoods and suburbs were planned, the 17th-century canals of Amsterdam and the 19–20th century Defence Line of Amsterdam are on the UNESCO World Heritage List. As the commercial capital of the Netherlands and one of the top financial centres in Europe, Amsterdam is considered a world city by the Globalization.
The city is the capital of the Netherlands. Many large Dutch institutions have their headquarters there, and seven of the worlds 500 largest companies, including Philips and ING, are based in the city. In 2012, Amsterdam was ranked the second best city to live in by the Economist Intelligence Unit and 12th globally on quality of living for environment, the city was ranked 3rd in innovation by Australian innovation agency 2thinknow in their Innovation Cities Index 2009. The Amsterdam seaport to this day remains the second in the country, famous Amsterdam residents include the diarist Anne Frank, artists Rembrandt van Rijn and Vincent van Gogh, and philosopher Baruch Spinoza. The Amsterdam Stock Exchange, the oldest stock exchange in the world, is located in the city center. After the floods of 1170 and 1173, locals near the river Amstel built a bridge over the river, the earliest recorded use of that name is in a document dated October 27,1275, which exempted inhabitants of the village from paying bridge tolls to Count Floris V.
This allowed the inhabitants of the village of Aemstelredamme to travel freely through the County of Holland, paying no tolls at bridges, the certificate describes the inhabitants as homines manentes apud Amestelledamme. By 1327, the name had developed into Aemsterdam, Amsterdam is much younger than Dutch cities such as Nijmegen and Utrecht. In October 2008, historical geographer Chris de Bont suggested that the land around Amsterdam was being reclaimed as early as the late 10th century. This does not necessarily mean there was already a settlement then, since reclamation of land may not have been for farming—it may have been for peat. Amsterdam was granted city rights in either 1300 or 1306, from the 14th century on, Amsterdam flourished, largely from trade with the Hanseatic League
Edward Francis Twining, Baron Twining GCMG MBE KStJ, known as Sir Edward Twining from 1949 to 1958, was a British diplomat, formerly Governor of North Borneo and Governor of Tanganyika. He was a member of the Twining tea family, in 1960 he published a book titled A History of the Crown Jewels of Europe, at over 700 pages it is probably the most extensive book on the subject. Twining was born in 1899 in Westminster to William Henry Greaves Twining and his wife, Agatha Georgina and his brother Stephan Twining became the managing director of the tea merchants, Twinings. He attended Lancing before training at the Royal Military College, Sandhurst and he married Helen Mary, daughter of Arthur Edmund Du Buisson, in 1928 and they had two sons. He served in Dublin with the Worcestershire Regiment between 1919 and 1922, inadvertently capturing Éamon de Valera in 1921 and he was appointed MBE for his services in Ireland. He entered the administrative service following two tours of Uganda with the 4th Kings African Rifles, returning there in 1929 as an assistant district commissioner.
He moved to Mauritius as director of labour in 1939, before becoming administrator in St Lucia in 1943, he was appointed Companion of the Order of St Michael, Twining served as Governor of North Borneo from November 1946. In 1949 he was promoted to KCMG and became Governor of Tanganyika and he was promoted to GCMG in 1953 and following his retirement, he became a life peer as Baron Twining, of Tanganyika and of Godalming in the County of Surrey, on 22 August 1958. He was appointed a Knight of the Venerable Order of Saint John in 1950 and he served as Honorary Colonel to 6th Battalion Kings African Rifles from 1955 to 1958. A History of the Crown Jewels of Europe, hansard 1803–2005, contributions in Parliament by Mr Francis Twining
Count Grigory Grigoryevich Orlov was the favorite of Empress Catherine the Great of Russia who presumably fathered her son. He led the coup which overthrew Catherines husband Peter III of Russia, for some years, he was virtually co-ruler with her, but his repeated infidelities and the enmity of Catherines other advisers led to his fall from power. He was the son of Gregory Orlov, governor of Great Novgorod and he was educated in the corps of cadets at Saint Petersburg, began his military career in the Seven Years War, and was wounded at Zorndorf. After the event, Empress Catherine raised him to the rank of count and made him adjutant-general, director-general of engineers and they had two illegitimate children and Aleksey, who were born in 1761 and 1762, respectively. The son was named after the village of Bobriki where he lived, Orlovs influence became paramount after the discovery of the Khitrovo plot to murder the whole Orlov family. At one time, the Empress thought of marrying her favorite, Orlov was no statesman, but he had a quick wit, a fairly accurate appreciation of current events, and was a useful and sympathetic counselor during the earlier portion of Catherines reign.
He entered with enthusiasm, both from patriotic and from economical motives, into the question of the improvement of the condition of the serfs and he was one of the earliest propagandists of the Slavophile idea of the emancipation of the Christians from Ottoman rule. Meanwhile, Orlovs enemies, led by Panin, were attempting to break up the relationship between Orlov and Catherine and they informed the empress that Orlov had seduced his 13-year-old relative. A handsome young officer, Alexander Vasilchikov, was installed as her new lover, to rekindle Catherines affection, Grigory presented to her one of the greater diamonds of the world, known ever since as the Orlov Diamond. By the time he returned - without permission - to his Marble Palace at Saint Petersburg, when Potemkin, in 1774, superseded Vasilchikov as the queens lover, Orlov became of no account at court and went abroad for some years. He returned to Russia a few prior to his death. In 1777, at the age of 43, he married his 18-year-old relative, Catherine Zinovyeva, variously described by sources as either a niece or a cousin, Catherine died of tuberculosis in 1783, at the age of 22.
For some time before his death, he suffered from a mental illness, probably a form of dementia. After his death, Catherine wrote, Although I have long been prepared for this sad event, people may console me, I may even repeat to myself all those things which it is customary to say on such occasions--my only answer is strangled tears
Diamond is a metastable allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the rate from diamond to graphite is negligible at standard conditions. Diamond is renowned as a material with superlative physical qualities, most of which originate from the covalent bonding between its atoms. In particular, diamond has the highest hardness and thermal conductivity of any bulk material and those properties determine the major industrial application of diamond in cutting and polishing tools and the scientific applications in diamond knives and diamond anvil cells. Because of its extremely rigid lattice, it can be contaminated by very few types of impurities, such as boron, small amounts of defects or impurities color diamond blue, brown, purple, orange or red. Diamond has relatively high optical dispersion, most natural diamonds are formed at high temperature and pressure at depths of 140 to 190 kilometers in the Earths mantle.
Carbon-containing minerals provide the source, and the growth occurs over periods from 1 billion to 3.3 billion years. Diamonds are brought close to the Earths surface through deep volcanic eruptions by magma, Diamonds can be produced synthetically in a HPHT method which approximately simulates the conditions in the Earths mantle. An alternative, and completely different growth technique is chemical vapor deposition, several non-diamond materials, which include cubic zirconia and silicon carbide and are often called diamond simulants, resemble diamond in appearance and many properties. Special gemological techniques have developed to distinguish natural diamonds, synthetic diamonds. The word is from the ancient Greek ἀδάμας – adámas unbreakable, the name diamond is derived from the ancient Greek αδάμας, unalterable, untamed, from ἀ-, un- + δαμάω, I overpower, I tame. Diamonds have been known in India for at least 3,000 years, Diamonds have been treasured as gemstones since their use as religious icons in ancient India.
Their usage in engraving tools dates to early human history, in 1797, the English chemist Smithson Tennant repeated and expanded that experiment. By demonstrating that burning diamond and graphite releases the same amount of gas, the most familiar uses of diamonds today are as gemstones used for adornment, a use which dates back into antiquity, and as industrial abrasives for cutting hard materials. The dispersion of light into spectral colors is the primary gemological characteristic of gem diamonds. In the 20th century, experts in gemology developed methods of grading diamonds, four characteristics, known informally as the four Cs, are now commonly used as the basic descriptors of diamonds, these are carat, cut and clarity. A large, flawless diamond is known as a paragon and these conditions are met in two places on Earth, in the lithospheric mantle below relatively stable continental plates, and at the site of a meteorite strike. The conditions for diamond formation to happen in the mantle occur at considerable depth corresponding to the requirements of temperature and pressure