In mineralogy, diamond (from the ancient Greek αδάμας – adámas "unbreakable") is an 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 conversion rate from diamond to graphite is negligible at ambient conditions. Diamond is renowned as a material with superlative physical qualities, most of which originate from the strong covalent bonding between its atoms. In particular, diamond has the highest hardness and thermal conductivity of any bulk material. 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.
Diamond has remarkable optical characteristics. Because of its extremely rigid lattice, it can be contaminated by very few types of impurities, such as boron and nitrogen. Combined with wide transparency, this results in the clear, colorless appearance of most natural diamonds. Small amounts of defects or impurities (about one per million of lattice atoms) color diamond blue (boron), yellow (nitrogen), brown (lattice defects), green (radiation exposure), purple, pink, orange or red. Diamond also has relatively high optical dispersion (ability to disperse light of different colors), which results in its characteristic luster. Excellent optical and mechanical properties, combined with efficient marketing, make diamond the most popular gemstone.
Most natural diamonds are formed at high temperature and pressure at depths of 140 to 190 kilometers (87 to 120 mi) in the Earth's mantle. Carbon-containing minerals provide the carbon source, and the growth occurs over periods from 1 billion to 3.3 billion years (25% to 75% of the age of the Earth). Diamonds are brought close to the Earth′s surface through deep volcanic eruptions by a magma, which cools into igneous rocks known as kimberlites and lamproites. Diamonds can also be produced synthetically in a high-pressure high-temperature process which approximately simulates the conditions in the Earth mantle. An alternative, and completely different growth technique is chemical vapor deposition (CVD). 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 been developed to distinguish natural and synthetic diamonds and diamond simulants.
Other articles related to "diamond":
... On December 18, 1931, Diamond's enemies finally caught up with him, shooting him after he had passed out at a hideout at 67 Dove Street in Albany, New York after a night party on the day of his trial in Troy, New York ... Party Chairman Dan O'Connell, who ran the local political machine, ordered Diamond's execution, which was carried out by the Albany Police ... Legs Diamond...called up one day and said he wanted to go into the 'insurance' business here ...
... Jack "Legs" Diamond (born Jack Moran July 10, 1897 – December 18, 1931), also known as Gentleman Jack, was an Irish-American gangster in Philadelphia and ... associate of gambler Arnold Rothstein, Diamond survived a number of attempts on his life between 1916 and 1931, causing him to be known as the "clay pigeon of the underworld" ... In 1930, Diamond's nemesis Dutch Schultz remarked to his own gang, "Ain't there nobody that can shoot this guy so he don't bounce back?" ...
11 September- The Marlborough diamond is stolen in London. 12 September - Marlborough diamond thieves Joseph Scalise and Arthur Rachel are arrested in Chicago after getting off a British Airways flight in the city ... However, the stolen diamond has not been found ...
... George Washington Carver born in Diamond, MO in 1864 ... American scientist, botanist, educator, and inventor ...
... The Diamond Lake neighborhood is in the Nokomis community in Minneapolis ... It is bounded by Diamond Lake Road and 55th Street on the north, Cedar Avenue on the east, 62nd Street on the south and Interstate 35W on the west ... The Diamond Lake neighborhood, together with Hale and Page, forms the HPDL Coordinates 44°53′42″N 93°15′39″W / 44.8951°N 93.2608°W / 44.8951 -93.2608 ...
Famous quotes containing the word diamond:
“A poet who makes use of a worse word instead of a better, because the former fits the rhyme or the measure, though it weakens the sense, is like a jeweller, who cuts a diamond into a brilliant, and diminishes the weight to make it shine more.”
—Horace Walpole (17171797)
“pulling off the fat diamond engagement ring,
pulling off the elopement wedding ring,
and holding them, clicking them
in thumb and forefinger,
the indent of twenty-five years,
like a tiny rip leaving its mark....”
—Anne Sexton (19281974)
“I met Jack Kennedy in November, 1946.... We went out on a double date and it turned out to be a fair evening for me. I seduced a girl who would have been bored by a diamond as big as the Ritz.”
—Norman Mailer (b. 1923)