Diamond natural, history

Smithsonian FAQ s Hope Diamond. National Museum of Natural History, Smithsonian Institution, http //www.si.edu/resource/faq/nmnh/hope.htm... 

The Nature of Diamonds. American Museum of Natural History, http //www.amnh.org/exhibitions/diamonds/... 

Figure 4.3.1 The Hope Diamond is the world s largest blue diamond and is on display in the National Museum of Natural History at the Smithsonian Institution. Photo reprinted with permission. 

For example, in the lengthy Natural History [2], by the famous Roman natural historian Gains Plinius Secundus, there are descriptions of polyhedral forms of beryl, rock-crystal, diamond, etc. 

Traditionally, synthetic diamonds are made from graphite. Since the 1950s, scientists have known how to use pressure and heat to manufacture synthetic diamonds. Gradually, the quality of the synthetic gems has improved. Today, it is difficult to tell a good synthetic diamond from a natural stone. According to the American Museum of Natural History, currently about 80 tons of synthetic diamonds are manufactured each year. 

Diamond J. "The Mvsicrious Origin of AIDS." Natural History. 24 [September 19921. 

It will be observed that all of the meteorites contain, in addition to nickel, a small quantity of cobalt, whilst the carbon content is extremely small. Carbon is sometimes present in meteoric iron in the form of minute diamonds.2 The Rowton specimen is interesting as being the first sidente observed to fall in Great Britain, and may be seen in the Natural History Museum, South Kensington. The Perryville siderite is the first recorded instance of the presence of ruthenium in meteoric iron. In addition to traces of this element, traces of iridium, palladium, and platinum were detected. 

Research investigate the history of diamonds—natural and synthetic. Explain the differences between them and their uses. Share your findings with the class. 

Figure 1.2 The blue Hope diamond kept in the National Museum of Natural History in Washington counts among the world s most famous diamonds ( Kowloonese 2004).

Hope diamond in National Museum of Natural History. Picture taken in April... 

What is the most famous diamond in the world What is the most visited piece of artwork apart from the Mona Lisa To what diamond was attributed the curse that brought about the executions of Louis XVI and Marie Antoinette What diamond appreciated over 100 times its original valuation during the course of the twentieth century What diamond was donated by Harry Winston to the Smithsonian National Museum of Natural History What diamond contains boron impurities within its carbon lattice that confers on it a deep blue color, its... 

What I hope to have added to the discussion has been a philosophical reflection on the nature of the concept of element and in particular an emphasis on elements in the sense of basic substances rather than just simple substances. The view of elements as basic substances, is one with a long history. The term is due to Fritz Paneth, the prominent twentieth century radio-chemist. This sense of the term element refers to the underlying reality that supports element-hood or is prior to the more familiar sense of an element as a simple substance. Elements as basic substances are said to have no properties as such although they act as the bearers of properties. I suppose one can think of it as a substratum for the elements. Moreover, as Paneth and before him Mendeleev among others stressed, it is elements as basic substances rather than as simple substances that are summarized by the periodic table of the elements. This notion can easily be appreciated when it is realized that carbon, for example, occurs in three main allotropes of diamond, graphite and buckminsterfullenes. But the element carbon, which takes its place in the periodic system, is none of these three simple substances but the more abstract concept of carbon as a basic substance. 

Koscheev A. P., Gromov M. D., Mohapatra M. K., and Ott U. (2001) History of trace gases in presolar diamonds as inferred from ion implantation experiments. Nature 412, 615-617. 

In Group 14, only carbon and tin exist as allotropes under normal conditions. For most of recorded history, the only known allotropes of carbon were diamond and graphite. Both are polymeric solids. Diamond forms hard, clear, colorless crystals, and was the first element to have its structure determined by x-ray diffraction. It has the highest melting point and is the hardest of the naturally occurring solids. Graphite, the most thermodynamically stable form of carbon, is a dark gray, waxy solid, used extensively as a lubricant. It also comprises the lead in pencils. 

Kuroda PK (1960) Nnclear fission in the early history of the earth. Nature 187 36-40 Lewis RS (1975) Rare gases in separated whitlockite from the St. Severin chondrite Xenon and krypton from fission of extinct " " Pu. Geochim Cosmochim Acta 39 417-432 Lewis RS, Ming T, Wacker JF, Steele IM (1987) Interstellar diamonds in meteorites. Nature 326 160-162 Lipschutz ME, Gaffey ME, Pellas P (1989) Meteorite parent bodies nature, number, size and relation to present-day asteroids. In Asteroids 11. Binzel RP, Gehrels T, Matthews MS (eds) University of Arizona, Tucson, p 740-788... 

Ozima M, Zashu S (1988) Solar-type Ne in Zaire cubic diamonds. Geochim Cosmochim Acta 52 19-25 Ozima M, Podosek FA, Igarashi G (1985) Terrestrial xenon isotope constraints on the early history of the Earth. Nature 315 471-474... 

Carbon has two stable isotopes, C and C. Natural diamond has 6 C-values between -3 and -5. Diamonds have been formed from carbon in the mantle with an isotopic composition that can be supposed to be in accordance with what existed for the newly created planet earth. The isotopic composition for carbon in meteorites also corresponds to a 6 C-value of -5%o. Inorganic carbonate sediments have the value 0 while organic sediments have the value -25%o. To give a total mean value of-5 the latter must constitute 20% of all sedimentary carbon. Modem estimates [4.9] assert that this value has been constant in almost 4 billion years. That implies that living organisms have been active since very early in the history of our planet... 

But surely, one of the most auspicious events in Florentine scientific history was the buming-lens experiment by Giuseppe Averani and Cipriano Targioni that revealed the true nature of diamond. It also set the stage for Lavoisier s more famous demonstration a century later that demolished the phlogiston theory and replaced it with his theory of combustion. 

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