carats

The Argyle diamond mine is a diamond mine located in Australia. The Argyle mine is the largest diamond producer in the world by volume, although due to the low proportion of gem-quality diamonds, is not the leader by value. It is the only known significant source of pink diamonds, producing 90 to 95 % of the world's supply. The Argyle diamond mine is also notable for being the first commercial diamond mine exploiting a volcanic pipe of lamproite, rather than the more usual kimberlite pipe. The mine is owned by the Rio Tinto Group, a d ...

Including:

• Argyle diamond mine - Description
• Argyle diamond mine - Location
• Argyle diamond mine - Geology
• Argyle diamond mine - Production
• Argyle diamond mine - Diamond characteristics
• Argyle diamond mine - Reserves
• Argyle diamond mine - Economics
• Argyle diamond mine - History

Read more here: » Argyle diamond mine: Encyclopedia - Argyle diamond mine

The Cullinan Diamond, found by Frederick Wells, surface manager of the Premier Diamond Mining Company in Cullinan, Gauteng, South Africa on June 25 1905, is the largest rough gem-quality diamond ever found, at 3,106.75 carats (621.35 g). Although a carbonado found in Brazil weighed more than 3,600 carats (720 g), no gem-quality material could be extracted from it. The stone was named after Sir Thomas Cullinan, the owner of the diamond mine. The stone was bought by the Transvaal government and presented to King Edward VII. It wa ...

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Diamond is one of the two best known forms (or allotropes) of carbon, whose hardness and high dispersion of light make it useful for industrial applications and jewelry (the other equally well known allotrope is graphite). Diamonds are specifically renowned as a mineral with superlative physical qualities - they make excellent abrasives because they can only be scratched by other diamonds, which also means they hold a polish extremely well and retain luster. About 130 million carats (26,000 kg) are mined annually ...

Including:

• Diamond - Material properties
• Diamond - Mechanical properties
• Diamond - Electromagnetic properties
• Diamond - Media
• Diamond - Natural history
• Diamond - Formation
• Diamond - Surfacing
• Diamond - Gemological characteristics
• Diamond - Carat
• Diamond - Clarity
• Diamond - Color
• Diamond - Cut
• Diamond - Cleaning
• Diamond - History
• Diamond - Record-holding diamonds
• Diamond - The diamond industry
• Diamond - Gem diamond industry
• Diamond - Industrial diamond industry
• Diamond - Diamond supply chain
• Diamond - Synthetics simulants and enhancements
• Diamond - Symbolism

Read more here: » Diamond: Encyclopedia - Diamond

Cubic Zirconia (or CZ) is zirconium oxide (ZrO2), a mineral that is extremely rare in nature but is widely synthesized for use as a diamond simulant. The synthesized material is hard, optically flawless and usually colorless, but may be made in a variety of different colors. It should not be confused with zircon, which is a zirconium silicate (ZrSiO4). Because of its low cost, durability, and close visual likeness to diamond, synthetic cubic zirconia has remained the most gemologically and economica ...

Including:

• Cubic zirconia - Technical aspects
• Cubic zirconia - History
• Cubic zirconia - Synthesis
• Cubic zirconia - Innovations
• Cubic zirconia - CZ versus diamond

Read more here: » Cubic zirconia: Encyclopedia - Cubic zirconia

Ruby is a red gemstone, a variety of the mineral corundum (aluminium oxide) in which the color is caused mainly by chromium. Its name originates from ruber, Latin for red. Natural rubies are exceptionally rare, though artificial ones (sometimes called created ruby) can be manufactured which are comparatively inexpensive. Rubies are mined in Africa, Asia, Australia and Greenland. They are most often found in Myanmar, Sri Lanka and Thailand, though they have also been found in Montana and South Carolina. Sometimes s ...

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Sapphire is the single-crystal form of aluminium oxide (Al2O3), a mineral known as corundum. It can be found naturally as gemstones or manufactured in large crystal boules for a variety of applications. Sapphire - Sapphire gems. Sapphire is any gemstone-quality corundum. (The red variety of corundum is also known as ruby.) When color is not specified, sapphire refers to the blue variety. Pink, yellow, green, white, and parti-color (multi-colored) sapphires are oft ...

Including:

• Sapphire - Sapphire gems
• Sapphire - Synthetic sapphire for non-gemstone applications

Read more here: » Sapphire: Encyclopedia - Sapphire

An object is pure if it has no contamination or foreign material. In reference to precious metals, purity is a measure of what percentage of an alloy is the metal in question. Purity is generally measured in carats. In The X-files, Purity is the codename of the Black Oil virus Category: Metals ...

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The Hope Diamond's history can be traced to a blue diamond named "Tavernier Blue," which was originally mined from the Kollur mine in Golconda, India, and was a crudely cut triangle shape of 112 3/16 carats (22.44 g). French merchant traveler Jean-Baptiste Tavernier purchased it sometime in 1660 or 1661. The Hope Diamond is believed to be stolen from an eye of a sculpted idol of the Hindu god, Shiva . In 1668, Tavernier sold the diamond to King Louis XIV of France. Sieur Pitau, the court jeweller, cut it and produced a 67 1/8 c ...

See also:

Hope Diamond, Hope Diamond - French Blue, Hope Diamond - Hope Family, Hope Diamond - Road to USA, Hope Diamond - Smithsonian years, Hope Diamond - The Curse, Hope Diamond - Popular Culture, Hope Diamond - Books

Read more here: » Hope Diamond: Encyclopedia II - Hope Diamond - French Blue

The Hope Diamond's history can be traced to a blue diamond named the Tavernier Blue, which was originally mined from the Kollur mine in Golconda, India, and was a crudely cut triangle shape of 112 3/16 carats (22.44 g). French merchant traveler Jean-Baptiste Tavernier purchased it sometime in 1660 or 1661. The Hope Diamond is believed to be stolen from an eye of a sculpted idol of the Hindu god, Shiva . In 1668, Tavernier sold the diamond to King Louis XIV of France. Sieur Pitau, the court jeweller, cut it and produced a 67 1/8 ...

See also:

Hope Diamond, Hope Diamond - French Blue, Hope Diamond - Hope Family, Hope Diamond - Road to USA, Hope Diamond - Smithsonian years, Hope Diamond - The Curse, Hope Diamond - Popular Culture, Hope Diamond - Books

Read more here: » Hope Diamond: Encyclopedia II - Hope Diamond - French Blue

Sapphire is any gemstone-quality corundum that is not red. (The red variety of corundum is also known as ruby.) When color is not specified, sapphire refers to the blue variety. Pink, yellow, green, white, and parti-color (multi-colored) sapphires are often valued less than the blue variety of the same quality and size. However a pink-orange sapphire, called a padparadsha, is highly prized. They were found in many countries especially in Asia such as India, S ...

See also:

Sapphire, Sapphire - Sapphire gems, Sapphire - Synthetic sapphire for non-gemstone applications, Sapphire - Historical/mythical usage

Read more here: » Sapphire: Encyclopedia II - Sapphire - Sapphire gems

List of world records - History. Largest empire: British Empire, 37 million km² (1912) Battles Largest naval battle: Matter of definition, see Largest naval battle in history List of world records - Media. Longest-running radio show: Rambling with Gambling (1925-2000), host ...

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List of world records, List of world records - Human mental and physical achievement and traits, List of world records - Anatomy, List of world records - Physiology, List of world records - Culture and society, List of world records - History, List of world records - Media, List of world records - Movie, List of world records - Music, List of world records - Painting, List of world records - Political entities, List of world records - Sculpture, List of world records - Man-made objects, List of world records - Buildings, List of world records - Transportation, List of world records - Places of worship, List of world records - Physical phenomena, List of world records - Geography, List of world records - Geology, List of world records - Biological phenomenona, List of world records - General records, List of world records - Animals, List of world records - Bacteria and archea, List of world records - Plants

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The use of diamonds as gemstones of decorative value is the most familiar use to most people today, and is also the earliest use, with decorative use of diamonds stretching back into antiquity. The dispersion of white light into a rainbow of colors, known in the trade as fire, is the other primary characteristic of gem diamonds, and has been highly prized throughout history. Over time, especially since around 1900, experts in the field of gemology have developed methods of characterizing diamonds and other gemstones based on th ...

See also:

Diamond, Diamond - Material properties, Diamond - Mechanical properties, Diamond - Electromagnetic properties, Diamond - Media, Diamond - Natural history, Diamond - Formation, Diamond - Surfacing, Diamond - Gemological characteristics, Diamond - Carat, Diamond - Clarity, Diamond - Color, Diamond - Cut, Diamond - Cleaning, Diamond - History, Diamond - Record-holding diamonds, Diamond - The diamond industry, Diamond - Gem diamond industry, Diamond - Industrial diamond industry, Diamond - Diamond supply chain, Diamond - Synthetics simulants and enhancements, Diamond - Symbolism

Read more here: » Diamond: Encyclopedia II - Diamond - Gemological characteristics

There are a variety of drill mechanisms which can be used to sink a borehole into the ground. Each has its advantages and disadvantages, in terms of the depth to which it can drill, the type of sample returned, the costs involved and penetration rates achieved. There are two basic types of drills - ones which produce rock chips or ones which produce core. Auger Drilling Auger drilling is achieved by means of a helical screw which is driven into the ground with rotation; the earth is lifted up the borehole by the blade of ...

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Boring mechanical, Boring mechanical - Drill Types, Boring mechanical - History, Boring mechanical - Limits of the technology, Boring mechanical - Causes of deviation, Boring mechanical - The Mohole, Boring mechanical - Boring 1911 Encyclopedia Brittanica

Read more here: » Boring mechanical: Encyclopedia II - Boring mechanical - Drill Types

The color of a diamond can be artificially altered by three distinct methods: irradiation with high-energy subatomic particles; the application of thin films or coatings; and the combined application of high temperature and high pressure (HTHP). The first two methods can only modify color, usually to turn an off-color Cape series stone (see Material properties of diamond: Composition and color) into a more desirable fancy-colored stone. Because some irradiation methods produce only a thin "skin" of color, they are applied to diamonds ...

See also:

Diamond enhancement, Diamond enhancement - Clarity enhancements, Diamond enhancement - Laser drilling, Diamond enhancement - Fracture filling, Diamond enhancement - Color enhancements, Diamond enhancement - Irradiation, Diamond enhancement - Coatings, Diamond enhancement - High-temperature high-pressure

Read more here: » Diamond enhancement: Encyclopedia II - Diamond enhancement - Color enhancements

Cubic zirconia is, as its name would imply, crystallographically isometric, and as diamond is also isometric, this is an important attribute of a would-be diamond simulant. Synthesized material contains a certain mole percentage (10-15%) of metal oxide stabilizer. During synthesis zirconium oxide would otherwise form monoclinic crystals, as that is its stable form under normal atmospheric conditions. The stabilizer is required for cubic crystal formation; it may be typically either yttrium or calcium oxide, the amount and stabilizer u ...

See also:

Cubic zirconia, Cubic zirconia - Technical aspects, Cubic zirconia - History, Cubic zirconia - Synthesis, Cubic zirconia - Innovations, Cubic zirconia - CZ versus diamond

Read more here: » Cubic zirconia: Encyclopedia II - Cubic zirconia - Technical aspects

Sapphire is any gemstone-quality corundum. (The red variety of corundum is also known as ruby.) When color is not specified, sapphire refers to the blue variety. Pink, yellow, green, white, and parti-color (multi-colored) sapphires are often valued less than the blue variety of the same quality and size. However a pink-orange sapphire, called a padparadsha, is highly prized. They were found in many countries especially in Asia such as India, S ...

See also:

Sapphire, Sapphire - Sapphire gems, Sapphire - Synthetic sapphire for non-gemstone applications

Read more here: » Sapphire: Encyclopedia II - Sapphire - Sapphire gems

The Argyle diamond mine leads the world in volume production of diamond, averaging annual production of 35 million carats (7,000 kg), or about one third of global production of natural diamonds. Production peaked in 1996, when 42 million carats (8,400 kg) were produced. Of this quantity only 5 % is considered gem-quality, with the rest being either near-gem quality or industrial grade; this is somewhat below world averages of about 20 % of mined diamonds qualifying as gem-grade. Since the mine's opening in 1985, it has produced ...

See also:

Argyle diamond mine, Argyle diamond mine - Description, Argyle diamond mine - Location, Argyle diamond mine - Geology, Argyle diamond mine - Production, Argyle diamond mine - Diamond characteristics, Argyle diamond mine - Reserves, Argyle diamond mine - Economics, Argyle diamond mine - History

Read more here: » Argyle diamond mine: Encyclopedia II - Argyle diamond mine - Production

In the 1970's and early 1980's the USSR attempted to drill a hole through the crust, to sample the Mohorivicic Discontinuity. The deepest hole ever drilled failed not because of lack of money or time, but because of the physics of rocks within the crust. The hole achieved approximately 12,000 metres depth, a depth at which rock begins to act more like a plastic solid than a rigid solid. The rock also approached temperatures of several hundred degrees celsius, requiring that the drilling fluid was refrigerated before being sent to the cutting ...

See also:

Boring mechanical, Boring mechanical - Drill Types, Boring mechanical - History, Boring mechanical - Limits of the technology, Boring mechanical - Causes of deviation, Boring mechanical - The Mohole, Boring mechanical - Boring 1911 Encyclopedia Brittanica

Read more here: » Boring mechanical: Encyclopedia II - Boring mechanical - The Mohole

Until the advent of internal combustion engines in the late 19th century, the primary method for drilling rock involved muscle power be it human or animal. Rods were turned by hand, using clamps attached to the rod. The rope and drop method, invented in China utilised a steel rod or piston raised and dropped vertically via a rope. Mechanised versions of this persisted until ~1970, utilising a cam to rapidly rai ...

See also:

Boring mechanical, Boring mechanical - Drill Types, Boring mechanical - History, Boring mechanical - Limits of the technology, Boring mechanical - Causes of deviation, Boring mechanical - The Mohole, Boring mechanical - Boring 1911 Encyclopedia Brittanica

Read more here: » Boring mechanical: Encyclopedia II - Boring mechanical - History

The mine covers about 450,000 square metres (110 acres), stretching in a mostly linear shape about 1600 metres (5,200 ft) long and 150 to 600 metres (500 to 2,000 ft) wide. The mine is of open pit construction, and reaches about 600 metres (1,900 ft) deep at its deepest point. Argyle diamond mine - Location. The Argyle diamond mine is located in the Kimberley region in the far northeast of the Australian state of Western Australia. It is located to the southwest of Lake Argyle in the Matsu Ranges, about 55 ...

See also:

Argyle diamond mine, Argyle diamond mine - Description, Argyle diamond mine - Location, Argyle diamond mine - Geology, Argyle diamond mine - Production, Argyle diamond mine - Diamond characteristics, Argyle diamond mine - Reserves, Argyle diamond mine - Economics, Argyle diamond mine - History

Read more here: » Argyle diamond mine: Encyclopedia II - Argyle diamond mine - Description