diamonds

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Diamonds

“diamond” from the Ancient Greek term “adamas”, which means indestructible

and unconquerable.

History► Diamonds were mined in India around 800 BC

► Diamonds were not mined when they were first found. They were found along rivers.

► In 1456 Louis de Bergueur discovered how to cut facets of a diamond.

► Until the 18th century India was the only known source for diamonds.

► Now diamonds are exported mostly from South Africa by a company called the De Beers.

Diamond Physical Properties► Hardness: Hardest gemstone known to man

► Clarity: Diamonds are transparent over a larger range of wavelengths

► Thermal Conductivity: Diamonds conduct heat better than anything else

► Melting Point: Diamond has the highest melting point (3820 degrees Kelvin)

► Lattice Density: The atoms of Diamonds in a tighter formation than any other substance.

Natural Diamonds

► they are formed deep inside the earth's interior (high pressure and heat create the diamond crystal lattice)

► through the eruptions they were transported to the

earth's surface.

► the eruptions were so fast and so powerful that the diamonds were brought straight to the surface.

Synthetic Diamonds

► they were first produced in 1953 in Sweden

► they have been made by a process called High Pressure High Temperature synthesis (HPHT)

► at this process graphite is put into a huge hydraulic press at high temperatures and pressures, and with the addition of a metallic catalyst, converts to diamond over a period of a few hours.

► the diamond crystals that are produced by this method are useful as hard-wearing edges on cutting tools.

Diamonds► Structure: carbon ► Constitution: cubic system► Colour: colourless, yellow, brown, green, blue, black ► Cut: white ► Hardness: 10 ► Density: 3,5 ► Other characters: the most adamant matter► Finding place: South Africa, Russia, Brasil► Availability: jewellery, hard-wearing edges on cutting

tools

Structure of Diamonds

► Diamond is carbon in its most concentrated form.

► Except for trace impurities like boron and nitrogen, diamond is composed solely of carbon.

Carbon

► Classification: non-metallic ► Symbol: C (lat. Carboneum)

► Atomic number: 6

► Group number: 14

► Atomic weight: 12.0107 ► Electron configuration: 1s2 2s2 2p2

► Electrons per shell: 2, 4

Structure of diamond

The carbon atom is connected to 4 other carbon atoms by strong chemical bonds, creating diamond's rigid crystal structure.

Shapes of crystals

► octahedron ► cubo-octahedron (a combined form)► dodecahedron ► macle twin ► cube                                                                                                                                

The biggest synthetic diamond has 10 carat.

Famous cuts of Diamonds

round cut radiant cut princess cut

Diamond has an aversion to water

The Mohs scale of mineral hardness

1 Talc 2 Gypsum3 Calcite 4 Fluorite5 Apatite6 Orthoclase7 Quartz8 Topaz 9 Corundum10 Diamond

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