Diamond Properties : Statastics

The Greek word " Adamas " means unconquerable and indestructible. This is the origin of the word diamond. It is one of the most indestructible natural formations known to man. From this word and from the depths of the earth is derived the diamond.

The diamond is the oldest item one can ever own. Diamonds are pure carbon. It is one of the earth's most common elements. It is a simple material, found in graphite pencils and fireplace soot. Diamonds were formed, and crystallized eons ago under incredible heat and pressure deep in the earth.

Vital statastics of diamond are as follows:

Composition:	C (carbon)
Crystallographic Class:	Cubic -- hexoctahedral (highest of the symmetries)
Space Group:	Fd3m -- a = 3.57 A (cell edge)
Common Forms {indices}:	F Octahedron {111}, cube {100}, dodecahedron {110}, rounded variations
Twins:	Spinel-law common, yielding the flat triangular "macle"
Hardness:	10 Mohs' scale, 56-115 Knoop hardness number (GPa), 10,000 Brooks identer scale; octahedral face hardest, cube face softest
Cleavage:	Excellent parallel to octahedron face -- {111}
Density:	3.51 g/cm3 (or specific gravity = 3.51)
Luster:	Adamantine (diamond provides the definition for this kind of luster)
Colors:	Colorless, yellow, blue, and many others
Refractive Index:	2.4175 (in the yellow light of a sodium lamp)
Dispersion:	Large (0.044), leading to rainbow colors on refraction
Optical Transmission:	Transparent over broad spectrum of the electromagnetic spectrum; an excellent material for optical windows
Thermal Conductivity:	Superb -- 5-25 Watts/centimeter-degreesC (at 300 K); 4 times greater than copper, an excellent thermal conductor
Electrical Conductivity:	0 to ~ 100 ohm-cm (resistivity at 300 K) -- an insulator

Most diamonds are used for technical purposes due to their hardness. Gem quality diamonds are found in over 20 counties, mainly in Africa. The biggest diamond producer is South Africa, followed by Russia. Usually, diamonds appear as isolated octahedron crystals. Sometimes they may have rounded corners and slightly curved faces.

Microcrystalline diamonds with irregular or globular appearance are called Bort (or boart), while carbonado are roughly octahedral, cubic or rhombic dodecahedral, blackish, irregular microcrystalline aggregates. Both are valued for industrial applications because they are not as brittle as diamond crystals.

Frequently, diamonds have inclusions of olivine, sulfides, chrome-diopside, chrome-spinels, zircon, rutile, disthene, biotite, pyrope garnet and ilmenite. Transparent crystals are usually colorless, but sometimes may have various yellowish tints. Rarely, diamonds may be bright yellow, blue, pale green, pink, violet, and even reddish. Some diamonds are covered by translucent skin with a stronger color.

Diamonds become green and radioactive after neutron irradiation, and yellow after further heating. They become blue after irradiation with fast electrons. Diamonds have different hardnesses along their different faces. Diamonds from different deposits also have different hardnesses. This quality allows for the polishing of faceted diamonds by diamond powder.

Diamonds have high thermal conductivity, which allows it to be readily and positively distinguished from all simulated gemstones. The most expensive diamonds are those with perfect structure and absolutely colorless or slightly bluish-white color. Yellow tint reduces the price of the diamond significantly. Bright colored diamonds are extremely rare, and have exceptionally high prices.

Diamond is invariably 'the biggest and the best'. See the table that contains the general properties of diamond which are so potentially useful across many fields of science.

Other Properties of Diamond.