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Diamond Type
Diamond type is a method of scientifically classifying diamonds by the level and type of their chemical impurities. Diamonds are separated into five types: Type IaA, Type IaB, Type Ib, Type IIa, and Type IIb. The impurities measured are at the atomic level within the crystal lattice of carbon atoms and so, unlike inclusions, require an infrared spectrometer to detect. Different diamond types react in different ways to diamond enhancement techniques. Different types can coexist within a single stone; natural diamonds are often mixes of Type Ia and Ib, which can be determined by their infrared absorption spectrum. Types of diamond Type I Type I diamonds, the most common class, contain nitrogen atoms as their main impurity, commonly at a concentration of 0.1%. Type I diamonds absorb in both the infrared and ultraviolet region, from 320 nm. They also have a characteristic fluorescence and visible absorption spectrum (see Optical prope ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koh-i-Noor
The ; ), also spelled Koh-e-Noor, Kohinoor and Koh-i-Nur, is one of the largest cut diamonds in the world, weighing . It is currently set in the Crown of Queen Elizabeth The Queen Mother. The diamond originated in the Kollur mine in present day Andhra Pradesh, India. According to the colonial administrator Theo Metcalfe, there is "very meagre and imperfect" evidence of the early history of the Koh-i-Noor before the 1740s. There is no record of its original weight, but the earliest attested weight is 186 old carats (191 metric carats or 38.2 g). The first verifiable record of the diamond comes from a history by Muhammad Kazim Marvi of the 1740s invasion of Northern India by Afsharid Iran under Nader Shah. Marvi notes the Koh-i-Noor as one of many stones on the Mughal Peacock Throne that Nader looted from Delhi. The diamond then changed hands between various empires in south and west Asia, until being given to Queen Victoria after the Second Anglo-Sikh War and the Bri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Thermal Conductivity
The thermal conductivity of a material is a measure of its ability to heat conduction, conduct heat. It is commonly denoted by k, \lambda, or \kappa and is measured in W·m−1·K−1. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity. For instance, metals typically have high thermal conductivity and are very efficient at conducting heat, while the opposite is true for insulating materials such as mineral wool or Styrofoam. Metals have this high thermal conductivity due to free electrons facilitating heat transfer. Correspondingly, materials of high thermal conductivity are widely used in heat sink applications, and materials of low thermal conductivity are used as thermal insulation. The reciprocal of thermal conductivity is called thermal resistivity. The defining equation for thermal conductivity is \mathbf = - k \nabla T, where \mathbf is the heat flux, k is the thermal conductivity, and \nabla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionizing Radiation
Ionizing (ionising) radiation, including Radioactive decay, nuclear radiation, consists of subatomic particles or electromagnetic waves that have enough energy per individual photon or particle to ionization, ionize atoms or molecules by detaching electrons from them. Some particles can travel up to 99% of the speed of light, and the electromagnetic waves are on the high-energy portion of the electromagnetic spectrum. Gamma rays, X-rays, and the higher energy vacuum ultraviolet, ultraviolet part of the electromagnetic spectrum are ionizing radiation; whereas the lower energy ultraviolet, visible light, infrared, microwaves, and radio waves are non-ionizing radiation. Nearly all types of laser light are non-ionizing radiation. The boundary between ionizing and non-ionizing radiation in the ultraviolet area cannot be sharply defined, as different molecules and atoms ionize at Ionization energies of the elements (data page), different energies. The energy of ionizing radiation starts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Hole
In physics, chemistry, and electronic engineering, an electron hole (often simply called a hole) is a quasiparticle denoting the lack of an electron at a position where one could exist in an atom or crystal structure, atomic lattice. Since in a normal atom or crystal lattice the negative charge of the electrons is balanced by the positive charge of the atomic nucleus, atomic nuclei, the absence of an electron leaves a net positive charge at the hole's location. Holes in a metal or semiconductor crystal lattice can move through the lattice as electrons can, and act similarly to electric charge, positively-charged particles. They play an important role in the operation of semiconductor devices such as transistors, diodes (including light-emitting diodes) and integrated circuits. If an electron is excited into a higher state it leaves a hole in its old state. This meaning is used in Auger electron spectroscopy (and other x-ray techniques), in computational chemistry, and to explai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor
A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping levels are present in the same crystal, they form a semiconductor junction. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called " metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common semiconductor and is used in laser diodes, solar cells, microwave-frequency integrated circuits, and others. Silicon is a critical element for fabricating most electronic circuits. Semiconductor devices can display a range of different useful properties, such as passing current more easil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-type Semiconductor
P-type or type P may refer to: P-type * P-type orbit, type of planetary orbit in a binary system * P-type asteroid, type of asteroid * P-type semiconductor * MG P-type, a type of automobile * P-type ATPase, evolutionarily related ion and lipid pumps * P-Type (rapper), a South Korean rapper Type P * the Audi Type P, a car * a Type P thermocouple See also * For P (and Q) in propositional logic, see modus ponens. {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron
Boron is a chemical element; it has symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the boron group it has three valence electrons for forming covalent bonds, resulting in many compounds such as boric acid, the mineral sodium borate, and the ultra-hard crystals of boron carbide and boron nitride. Boron is synthesized entirely by cosmic ray spallation and supernovas and not by stellar nucleosynthesis, so it is a low-abundance element in the Solar System and in the Earth's crust. It constitutes about 0.001 percent by weight of Earth's crust. It is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest known deposits are in Turkey, the largest producer of boron minerals. Elemental boron is found in smal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Vapor Deposition
Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high-quality, and high-performance, solid materials. The process is often used in the semiconductor industry to produce thin films. In typical CVD, the wafer (electronics), wafer (substrate) is exposed to one or more Volatility (chemistry), volatile wikt:precursor, precursors, which chemical reaction, react and/or chemical decomposition, decompose on the substrate surface to produce the desired deposit. Frequently, volatile by-products are also produced, which are removed by gas flow through the reaction chamber. Microfabrication processes widely use CVD to deposit materials in various forms, including: Single crystal, monocrystalline, polycrystalline, amorphous, and Epitaxy, epitaxial. These materials include: silicon (Silicon dioxide, dioxide, silicon carbide, carbide, silicon nitride, nitride, silicon oxynitride, oxynitride), carbon (carbon (fiber), fiber, carbon nanofibers, nanofibers, carbon nanot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Diamond
A synthetic diamond or laboratory-grown diamond (LGD), also called a lab-grown, laboratory-created, man-made, artisan-created, artificial, or cultured diamond, is a diamond that is produced in a controlled technological process, in contrast to a naturally-formed diamond, which is created through geological processes and obtained by mining. Unlike diamond simulants (imitations of diamond made of superficially similar non-diamond materials), synthetic diamonds are composed of the same material as naturally formed diamonds—pure carbon crystallized in an isotropic 3D form—and have identical chemical and physical properties. The maximal size of synthetic diamonds has increased dramatically in the 21st century. Before 2010, most synthetic diamonds were smaller than half a carat. Improvements in technology, plus the availability of larger diamond substrates, have led to synthetic diamonds up to 125 carats in 2025.=https://www.gia.edu/gia-news-research/gems-gemology-summary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Lulo Rose
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] |
Lesedi La Rona
Lesedi La Rona, formerly known in media as Karowe AK6 or as Quad 1 by the personnel at the mine, is the fifth-largest diamond ever found, and the third-largest of gem quality. It was found in the Karowe mine, (formerly called AK6) in Botswana on 16November 2015. British jeweller Graff bought the rough diamond for $53 million in 2017. By April 2019, Graff had cut it into one large emerald cut diamond, the Graff Lesedi La Rona, weighing and 66 smaller stones. Description The Lesedi La Rona is a colourless/white, type IIa diamond. It weighs and measures . In comparison, the Cullinan, discovered in 1905 in South Africa, weighed . The Lesedi La Rona was mined using Large Diamond Recovery ("LDR") XRT machines, and is the largest diamond recovered using machines for automated diamond sorting. It is estimated to be over 2.5 billion years old. It was found on 16November 2015, in the South Lobe of the Karowe mine about below the surface, and the find was announced on 18November ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
