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Diamond Clarity
Diamond clarity is the quality of diamonds that relates to the existence and visual appearance of internal characteristics of a diamond called ''inclusions'', and surface defects, called ''blemishes''. Clarity is one of the four Cs of diamond grading, the others being carat, color, and cut. Inclusions are solids, liquids, or gases that were trapped in a mineral as it formed. They may be crystals of a foreign material or even another diamond crystal, or may have produced structural imperfections, such as tiny cracks that make a diamond appear whitish or cloudy. The number, size, color, relative location, orientation, and visibility of inclusions can all affect the relative clarity of a diamond. A clarity grade is assigned based on the overall appearance of the stone under ten times magnification, which is the standard magnification for loupes used in the gem world. Most inclusions present in gem-quality diamonds do not affect the diamonds' performance or structural integrity an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Diamond
Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water. Another solid form of carbon known as graphite is the Chemical stability, chemically stable form of carbon at Standard temperature and pressure, room temperature and pressure, but diamond is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest Scratch hardness, hardness and thermal conductivity of any natural material, properties that are used in major industrial applications such as cutting and polishing tools. Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen). Small numbers of lattice defect, defects or impurities (about one per million of lattice atoms) can color ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Diamond (gemstone)
Diamond is a gemstone formed by diamond cut, cutting a raw diamond. Diamonds have high monetary value as one of the best-known and most sought-after gems, and they have been used as decorative items since ancient times. The hardness of diamond and its high Dispersion (optics), dispersion of light—giving the diamond its characteristic "fire"—make it useful for industrial applications and desirable as jewelry. Diamonds are such a highly traded commodity that multiple organizations have been created for grading and certifying them based on the "four Cs", which are color, cut, clarity, and carat. Other characteristics, such as presence or lack of fluorescence, also affect the desirability and thus the value of a diamond used for jewelry. Diamonds often are used in engagement rings. The practice is documented among European aristocracy as early as the 15th century, though ruby and sapphire were more desirable gemstones. The modern popularity of diamonds was largely created by D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
International Gemological Institute
International Gemological Institute (IGI) is a gemological organization which certifies diamond, coloured stone and jewellery. It was established in 1975 in Belgium. On 21 May 2023, Blackstone Group announced their acquisition of IGI. History In March 2007, IGI collaborated with the Tanzanite Foundation to help distribute jewellery certificates using a grading scale called the Tanzanite Quality Scale (TQS), for the gem called Tanzanite, which was discovered in Tanzania in the 1960s. In April 2010, IGI marked the opening of their laboratory in Surat, their fifth diamond grading laboratory in India. Operations IGI has a staff of over 650 gemologists, appraisers and professional office personnel. IGI provides its services to the public through diamond dealers, and jewellery manufactures. IGI provides independent grading reports, coloured stone reports, identification and appraisal reports, diamond authentication and attestations of origin, and laser inscription services. They a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
List Of Diamonds
Diamond (gemstone), Diamonds occur naturally and vary in size, color, and quality, so the largest of a particular color may not be large in absolute terms, but may still be considered very desirable. Diamonds may also have high valuations in sale prices, and large ones invariably have a noteworthy ownership history. There is no agreed-upon measure of a large or a high-quality diamond, and new ones displace others on any subjective list, so strict inclusion criteria for notable diamonds are not attainable. List of diamonds See also * List of largest rough diamonds * List of Golconda diamonds * List of emeralds by size * List of individual gemstones * List of gold nuggets by size * List of pearls by size * List of sapphires by size References {{DEFAULTSORT:List Of Diamonds Diamond-related lists, Individual diamonds, * Gemstone-related lists, Diamonds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Diamond Color
A chemically pure and structurally perfect diamond (gemstone), diamond is perfectly transparent with no hue, or color. However, in reality almost no gem-sized natural diamonds are absolutely perfect. The color of a diamond may be affected by colors of chemicals, chemical impurities and/or structural defects in the Crystal structure#Lattice systems, crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value. For example, most colorless (white) diamonds are discounted in price when more yellow hue is detectable, while intense pink diamonds or blue diamonds (such as the Hope Diamond) can be dramatically more valuable. Of all colored diamonds, red diamonds are the rarest. The Aurora Pyramid of Hope displays a spectacular array of naturally colored diamonds, including red diamonds. History of color grading Color grading of diamonds was performed as a step of sorting rough diamonds for sale by the Londo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Blowtorch
A blowtorch, also referred to as a blowlamp, is an ambient air fuel-burning tool used for applying flame and heat to various applications, usually in metalworking, but occasionally for foods like crème brûlée. Description Early blowtorches used liquid fuel, carried in a refillable reservoir attached to the lamp. This is distinct from modern gas-fueled torches burning fuel such as a butane torch or propane torch. Their fuel reservoir is disposable or refillable by exchange. Liquid-fueled torches are pressurized by a piston hand pump, while gas torches are self-pressurized by the fuel evaporation. The term "blowtorch" is commonly misused as a name for any metalworking torch, but properly describes the pressurized liquid fuel torches that predate the common use of pressurized fuel gas cylinders. Torches are available in a vast range of size and output power. The term "blowtorch" applies to the obsolescent style of smaller liquid fuel torches. Blowtorches are typically a singl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Diamond Enhancement
Diamond enhancements are specific treatments, performed on natural diamonds (usually those already cut and polished into gems), which are designed to improve the visual gemological characteristics of the diamond in one or more ways. These include clarity treatments such as laser drilling to remove black carbon inclusions, fracture filling to make small internal cracks less visible, color irradiation and annealing treatments to make yellow and brown diamonds a vibrant fancy color such as vivid yellow, blue, or pink. The CIBJO and government agencies, such as the United States Federal Trade Commission, explicitly require the disclosure of all diamond treatments at the time of sale. Some treatments, particularly those applied to clarity, remain highly controversial within the industry—this arises from the traditional notion that diamonds hold a unique or "sacred" place among the gemstones, and should not be treated too radically, if for no other reason than a fear of damaging con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Market Liquidity
In business, economics or investment, market liquidity is a market's feature whereby an individual or firm can quickly purchase or sell an asset without causing a drastic change in the asset's price. Liquidity involves the trade-off between the price at which an asset can be sold, and how quickly it can be sold. In a liquid market, the trade-off is mild: one can sell quickly without having to accept a significantly lower price. In a relatively illiquid market, an asset must be discounted in order to sell quickly. A liquid asset is an asset which can be converted into cash within a relatively short period of time, or cash itself, which can be considered the most liquid asset because it can be exchanged for goods and services instantly at face value. Overview A liquid asset has some or all of the following features: it can be sold rapidly, with minimal loss of value, anytime within market hours. The essential characteristic of a liquid market is that there are always ready and wil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
International Diamond Council
The World Diamond Council is an organization representing the entire diamond value chain including representatives from diamond mining, manufacturing, trading and retail. The council was established in July 2000. The purpose was to create a system to keep the supply chain of diamonds as free as possible from conflict diamonds. In December 2000, the United Nations General Assembly adopted a landmark resolution supporting the creation of an international certification scheme for rough diamonds. By November 2002, negotiations between governments, the international diamond industry and civil society organisations resulted in the creation of the Kimberley Process Certification Scheme (KPCS). The KPCS document sets out the requirements for controlling rough diamond production and trade. The KPCS entered into force in 2003, when participating countries started to implement its rules. The KPCS is credited as being instrumental toward dramatically reducing “conflict diamonds” to less ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Aplanatic
In optics, spherical aberration (SA) is a type of aberration found in optical systems that have elements with spherical surfaces. This phenomenon commonly affects lenses and curved mirrors, as these components are often shaped in a spherical manner for ease of manufacturing. Light rays that strike a spherical surface off-centre are refracted or reflected more or less than those that strike close to the centre. This deviation reduces the quality of images produced by optical systems. The effect of spherical aberration was first identified in the 11th century by Ibn al-Haytham who discussed it in his work Kitāb al-Manāẓir. Overview A spherical lens has an aplanatic point (i.e., no spherical aberration) only at a lateral distance from the optical axis that equals the radius of the spherical surface divided by the index of refraction of the lens material. Spherical aberration makes the focus of telescopes and other instruments less than ideal. This is an important effect, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Achromatic Lens
An achromatic lens or achromat is a lens (optics), lens that is designed to limit the effects of chromatic aberration, chromatic and spherical aberration. Achromatic lenses are corrected to bring two wavelengths (typically red and blue) into focus on the same plane. Wavelengths in between these two then have better focus error than could be obtained with a simple lens. The most common type of achromat is the achromatic doublet, which is composed of two individual lenses made from glasses with different amounts of Dispersion (optics), dispersion. Typically, one element is a negative (Lens (optics)#Types of simple lenses, concave) element made out of flint glass such as F2, which has relatively high dispersion, and the other is a positive (Lens (optics)#Types of simple lenses, convex) element made of Crown glass (optics), crown glass such as BK7, which has lower dispersion. The lens elements are mounted next to each other, often cemented together, and shaped so that the chromati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Piqué
Pique or piqué may refer to: Arts and entertainment * Piqué (ballet), a dance movement * ''Pique'' (play), an 1875 play produced by Augustin Daly * "Pique", an episode of ''Law & Order: Special Victims Unit'' (season 2) Ships * HMS ''Pique'', seven ships of the Royal Navy * USS ''PC-1249'', a US Navy submarine chaser sold to France as ''Pique'' (W13) People * Piqué (surname) Other uses * Piqué (weaving), a weaving style * Pique (river), Haute-Garonne, southern France * Tungiasis, a skin parasite known as "pique" in much of South America * ''Pique Newsmagazine'', a Canadian magazine * Pique, the 1986 FIFA World Cup mascot * Piqué, a type of shot in artistic billiards * Pique (abstract algebra), a quasigroup with an idempotent element * Pique, the emotion of resentment Resentment (also called ranklement or bitterness) is a complex, multilayered emotion that has been described as a mixture of disappointment, disgust and anger. Other psychologists consider it a Moo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
