alexandrite natural of photo stone

Sort by:
Best match
- Keyword relevance
- Page rank relevance
Page title
- A to Z ascending
- Z to A descending
Most recent first
- Most recent last

241. Thermolumnescence: A variety of luminescence where certain rocks of minerals showing the property due to application of heat or infrared. Some diamonds exhibits blue thermoluminescence, when heated to about 200 C. Thermoluminescence emitted when the color traps are disappea; HTML, 24 Kb, 2008-07-20 13:07:05; /chapters/glossary/thermolumnescence.html
242. Thermochroism: The science of high temperature of one subject to change its color, because by increasing of temperature expands the bond length of lattice, reduced the ligand field. A red compound of 10% Cr2O3 and 90% Al2O3 by increasing the temperature to over 400 C th; HTML, 25 Kb, 2008-07-20 13:07:03; /chapters/glossary/thermochroism.html
243. Synthetic alexandrite: A misleading term for synthetic spinel or corundum (sapphire), which is able to change color like alexandrite reddish-green in daylight and reddish at artificially light, such stones were at first misnomered as scientific alexandrite. Synthetic sapphire; HTML, 24 Kb, 2008-07-20 13:07:00; /chapters/glossary/synthetic-alexandrite.html
244. Synthetic: Artificially made substance that has the same appearance, physical properties and chemical compound as its natural counterpart mineral. Some synthetic stones have no counterpart in nature they are synthetic gemstones except if they used as an imitation fo; HTML, 25 Kb, 2008-07-20 13:06:58; /chapters/glossary/synthetic.html
245. Spinel: An isomorphous mineral of spinel group. A wide range of colors and shade of gemstone. Red-orange is named as flame spinel, an iron-rich dark-green to black, which is known as green spinel, pleonaste or ceylonite, grass-green as chlorospinel (iron-rich), b; HTML, 26 Kb, 2008-07-20 13:06:56; /chapters/glossary/spinel.html
246. Spectrum: Any array of electromagnetic visible light ordered according to its constituent wavelengths or colors, when the white light is dispersed by a prism or diffraction grating, ranging from about 750 to about 400 nm. The spectra can obtained by means of spectr; HTML, 27 Kb, 2008-07-20 13:06:54; /chapters/glossary/spectrum.html
247. Spectroscope: A small hand optical device for obtaining and visually observing spectrum, in which collimated light passes through a narrow slit onto either a prism or diffraction grating, its spectrum being viewed by a lens system or telescope. The angle between the c; HTML, 24 Kb, 2008-07-20 13:06:53; /chapters/glossary/spectroscope.html
248. Specific gravity: The ratio of the weight of any substance to that of pure water at temperature of 3.98 C (39.2 F) degree and standard atmospheric pressure. Specific gravity of gems and minerals are determined by means by hydrostatic weighing method.; HTML, 24 Kb, 2008-07-20 13:06:51; /chapters/glossary/specific-gravity.html
249. Simulant: To simulate or imitate a natural gemstone, which is made from components that are easier, cheaper or more convenient to manufacture. Simulated stone having superficial appearance to the true stone but differs from it either in chemical composition, struct; HTML, 24 Kb, 2008-07-20 13:06:49; /chapters/glossary/simulant.html
250. Silica: Dioxide of silicon (SiO2), which appeared in five crystalline polymorphous such as quartz (alpha and beta), tridymite, cristobalite, coesite, and stichovite, in cryptocrystalline such as chalcedony and chert, and in amorphous such as opal (a hydrated sili; HTML, 25 Kb, 2008-07-20 13:06:47; /chapters/glossary/silica.html
251. Refractive index measurement: Several methods are available for the measurement of refractive indices such as refractometer for total reflection, immersion method in liquid for Beck effect, shadow method, and minimum deviation method.; HTML, 24 Kb, 2008-07-20 13:06:44; /chapters/glossary/refractive-index-measurement.html
252. Reflection: The turning back of wave from surface, on which they are incident according to the definite law of reflection. A small part of ray 17.2% of incident light striking the surface vertically is reflected from the surface (the 17.2% is upper limit of reflected; HTML, 25 Kb, 2008-07-20 13:06:42; /chapters/glossary/reflection.html
253. Ray: A narrow beam of light, which emanate from a single bright source that proceed in one direction.; HTML, 23 Kb, 2008-07-20 13:06:40; /chapters/glossary/ray.html
254. Radium fluorescence: Radium treatment of minerals such as beryl to produce a bluish-white fluorescence only on the basal planes. Under SWUV and LWUV light beryl fluoresces bluish-white.; HTML, 23 Kb, 2008-07-20 13:06:38; /chapters/glossary/radium-fluorescence.html
255. Radiation: The emission of particles or electromagnetic waves from a source such as nuclear radiation, X-rays, neutrons, gamma rays, electrons positive or negative, protons. Radiation has the effect of artificially altering color by artificially creating color cent; HTML, 24 Kb, 2008-07-20 13:06:36; /chapters/glossary/radiation.html
256. Quoin facets: The four quadrilateral facets of 8 main facets on the crown or on the pavilion of a brilliant-cut stone, which are also called bezel facets. The 4 on the crown touching the girdle with their apex and extending up to touch the table. There are four lozenge; HTML, 24 Kb, 2008-07-20 13:06:33; /chapters/glossary/quoin-facets.html
257. Quinoline: An oily colorless, specific odor, insoluble, basic heterocyclic with the formula C9H7N. Composed synthetically by heating aniline, nitrobenzene, glycerol, and sulfuric acid. Used as food preservative and in the manufacture of dyes and antiseptics. R.I. -; HTML, 24 Kb, 2008-07-20 13:06:31; /chapters/glossary/quinoline.html
258. Quench crackled synthetic corundum: An unusual feature occur in Verneuil synthetic corundum by plunging of still heated stone into a much cooler liquid (thermal shock), which create fractures and it resemble closely to natural stone. By pursuing of this process developed honeycomb pattern d; HTML, 24 Kb, 2008-07-20 13:06:29; /chapters/glossary/quench-crackled-synthetic-corundum.html
259. Quartz, cat's-eye: A variety of translucent, grayish-green to greenish yellow chatoyant quartz or chalcedony containing fine parallel fibers of asbestos or parallel channels, arranged through the stone at right angles to the eye and parallel to the base of the crystal, that; HTML, 24 Kb, 2008-07-20 13:06:27; /chapters/glossary/quartz-cat-s-eye.html
260. Quantum: Quantum of light or electromagnetic radiation, it can behave as a wave or as a particle. Traveling at the velocity of light. Photon have momentum but not mass or electrical charge. Also known as light quantum. Caused by excitation of atoms and molecules a; HTML, 25 Kb, 2008-07-20 13:06:25; /chapters/glossary/quantum.html
261. Physical properties: Physical properties of gemstones are extremely important in understanding geological phenomena in synthesizing new materials, and identification of minerals. Physical properties and chemical composition of minerals change with temperature and pressure. P; HTML, 24 Kb, 2008-07-20 13:06:22; /chapters/glossary/physical-properties.html
262. Phenomenon: A special optical occurrence, or circumstance observed or are visible in certain gemstones such as chatoyancy, asterism, or play of color, adularescence, girasol, labradorescence, opalescence, schiller, etc.; HTML, 24 Kb, 2008-07-20 13:06:20; /chapters/glossary/phenomenon.html
263. Phase: The sum of homogeneous, physically distinct portion of matter in heterogeneous system, as the three phases; solid, liquid, or gas. Each phase may exist in different temperatures and pressures.; HTML, 24 Kb, 2008-07-20 13:06:18; /chapters/glossary/phase.html
264. Perovskite: Prized by collectors. Synthetic strontium titanate or fabulite found in a similar manner to perovskite. Natural counterpart of fabulite with the same composition is called tausonite.; HTML, 23 Kb, 2008-07-20 13:06:16; /chapters/glossary/perovskite.html
265. Pegmatite: A light-colored, coarse-grained igneous rock from granite clan containing orthoclase, quartz, microline, mica, gemstones, and many ferromagnesian minerals resulting from slow solidification. Pegmatite is occurring place of many uncommon gem minerals such; HTML, 24 Kb, 2008-07-20 13:06:14; /chapters/glossary/pegmatite.html
266. Oxide: A binary composition of oxygen with metals or other elements.; HTML, 23 Kb, 2008-07-20 13:06:11; /chapters/glossary/oxide.html
267. Orientation crystal: The placing of atoms or radicals in a crystal so that they point in a definite direction, or its crystallographic axes are in the conventional position.; HTML, 23 Kb, 2008-07-20 13:06:09; /chapters/glossary/orientation-crystal.html
268. Oriental chrysoberyl: A misleading term for yellowish-green variety of sapphire.; HTML, 23 Kb, 2008-07-20 13:06:07; /chapters/glossary/oriental-chrysoberyl.html
269. Optical axis: A term used in crystallography to the direction of an anisotropic crystal along which there are no double reflection.; HTML, 23 Kb, 2008-07-20 13:06:05; /chapters/glossary/optical-axis.html
270. Opaque: Impenetrable to light. A stone is opaque, when light cannot passed through a thin-section of 0.04 mm. For example pyrite, cuprite, etc.; HTML, 23 Kb, 2008-07-20 13:06:03; /chapters/glossary/opaque.html
271. Novosibirsk synthetic alexandrite: Synthetic alexandrite made in three methods in Russia, (a) growing synthetic stones of solution-growth process or flux process specially for alexandrite, (b) Growing stone of floating-zone process. (c) Melt-grown process or so-called pulling method.; HTML, 24 Kb, 2008-07-20 13:06:00; /chapters/glossary/novosibirsk-synthetic-alexandrite.html
272. Negative reading: Testing a gemstone on a refractometer prism, when the stone has a greater refractive index than the measuring prism of the device, or higher than the refractive index of immersion liquid used for optical contact, the scale of refractometer remains dark an; HTML, 24 Kb, 2008-07-20 13:05:58; /chapters/glossary/negative-reading.html
273. Needlelike (silk): Acicular a needle form of inclusions in gemstones.; HTML, 23 Kb, 2008-07-20 13:05:56; /chapters/glossary/needlelike-silk.html
274. Natural: A mineral or substance, which occurs in nature; opposite of synthetic or man-made.; HTML, 23 Kb, 2008-07-20 13:05:53; /chapters/glossary/natural.html
275. Moh's hardness scale: The most commonly used ten standard scale of relative hardness of minerals. The scale is expressed in numbers ranging from 1 through 10: (1) talc, (2) gypsum, (3) calcite, (4) fluorite, (5) apatite, (6) orthoclase, (7) quartz, (8) topaz, (9) corundum, (10; HTML, 24 Kb, 2008-07-20 13:05:49; /chapters/glossary/moh-s-hardness-scale.html
276. Mineralogy: The scientific study of minerals; their formation, occurrence, chemical composition, physical properties, and their classification. Oryctognosy and oryctology are obsolete terms.; HTML, 23 Kb, 2008-07-20 13:05:47; /chapters/glossary/mineralogy.html
277. Mineral: A loose and inexact term that may be to define: usually homogeneous inorganic substance of definite physical properties and more or less chemical composition, which occur naturally in the earth, and usually possess a crystalline structure, which frequentl; HTML, 24 Kb, 2008-07-20 13:05:45; /chapters/glossary/mineral.html
278. Mica schist: Schist consisting largely of micas and quartz.; HTML, 23 Kb, 2008-07-20 13:05:44; /chapters/glossary/mica-schist.html
279. Metamorphic rock: Any rock, which has been derived from pre-existing rocks by mineralogical, chemical composition, textural and structural changing, essentially in the solid state due to processes operating in the earth's crust of heat or intense pressure, shearing stress,; HTML, 24 Kb, 2008-07-20 13:05:42; /chapters/glossary/metamorphic-rock.html
280. Magma: A naturally occurring molten or semi-molten material in suspension, with dissolved gases, generated within or beneath the earth's crust and capable of intrusion and extrusion. Magma, which is extruded on the surface of the earth is called lava.; HTML, 24 Kb, 2008-07-20 13:05:38; /chapters/glossary/magma.html
281. Luminescence: The emission of certain visible wavelengths of light from a substance other than thermal process, which are used as diagnostic determination of gemstones. It is caused by the emission of photons, when an exited atom within the substance returns to the gro; HTML, 25 Kb, 2008-07-20 13:05:35; /chapters/glossary/luminescence.html
282. Light absorption: In optics, the reduction of the light intensity in transmission through an absorbing substance or in reflection from a surface, in crystals, minerals and gems. Absorption may vary with wavelengths of vibration in the direction of the transmitted light or; HTML, 24 Kb, 2008-07-20 13:05:33; /chapters/glossary/light-absorption.html
283. Laser: An acronym of light amplification by stimulated emission of radiation. A device that emits UV to infra red electromagnetic energy, that is a nearly parallel, nearly monochromatic and coherent beam of light of very restricted diameter formed by causing exi; HTML, 25 Kb, 2008-07-20 13:05:31; /chapters/glossary/laser.html
284. Laminate: A rock or mineral in plate form consisting of several different layers bonded by or cemented together, which is separated or split into thin layers.; HTML, 23 Kb, 2008-07-20 13:05:27; /chapters/glossary/laminate.html
285. Kelvin temperature scale: A System International (SI) unit of thermodynamic temperature scale, commences at absolute zero, equal to 1/273.16 C degree.; HTML, 23 Kb, 2008-07-20 13:05:24; /chapters/glossary/kelvin-temperature-scale.html
286. Kashmir: Beautiful sapphire and rubies occur in various parts of Kashmir, Pakistan.; HTML, 23 Kb, 2008-07-20 13:05:22; /chapters/glossary/kashmir.html
287. Karat: In metallurgy a unit that expresses only to the purity of solid gold used in jewelry. In trade based on a scale of twenty-fourths, 24 karat means pure gold, 18 karat gold means, containing 18 parts gold to 6 parts of alloy, and 9 karat gold means, contain; HTML, 24 Kb, 2008-07-20 13:05:18; /chapters/glossary/karat.html
288. Jewels of India: Indian gem lore was from ancient times famous for its good quality and richness. There are several famous gems in other museums such as Timur Ruby, Koh-i-Nur Diamond, etc. Most famous part of Indian jewels was in possession oh Maharajah Duleep Singh.; HTML, 24 Kb, 2008-07-20 13:05:13; /chapters/glossary/jewels-of-india.html
289. Jewelry: A number of decorative articles made artistically of gold, platinum, silver, and precious stones that are worn for personal adornment, such as bracelets, rings, necklaces, etc.; HTML, 23 Kb, 2008-07-20 13:05:11; /chapters/glossary/jewelry.html
290. Jewel enamel: An enamel made of special porcelain used in jewelry as insignia and art objects.; HTML, 23 Kb, 2008-07-20 13:05:07; /chapters/glossary/jewel-enamel.html
291. Jewel: A fashioned ornament for personal adornment, which is made of noble metals mounted with natural, synthetic, or imitation gemstones.; HTML, 23 Kb, 2008-07-20 13:05:05; /chapters/glossary/jewel.html
292. Irradiation: The process of exposing certain diamond or other pale or poorly colored gemstone to radiation, such as in nuclear reactor, X-rays, neutrons from an atomic pile, deuterons a nucleus of the heavy hydrogen atom, gamma rays from a cobalt-60, electrons positiv; HTML, 25 Kb, 2008-07-20 13:05:02; /chapters/glossary/irradiation.html
293. Index of refraction: In crystal optics, a number indicating the speed of the velocity of light in a vacuum or air to its velocity in a given crystal. The refractive index (RI) of a crystal can be expressed as ratio of the sine of the angle of incidence to the sine of the angl; HTML, 25 Kb, 2008-07-20 13:05:00; /chapters/glossary/index-of-refraction.html
294. Inclusions: A general name for any small visible foreign matter such as gas, liquid, glass, or mineral enclosed within a gemstone or rock, which is a growth phenomena. Fracture or cleavage in a gemstone are not classed as inclusions. The nature of inclusions are used; HTML, 26 Kb, 2008-07-20 13:04:58; /chapters/glossary/inclusions.html
295. Inclusion in chrysoberyl: The chrysoberyl crystal is penetrated by microscopic tubes, two-phase or relatively short needles parallel to the vertical or c-axis of the crystal, suitable for cut en cabochon. In brown and yellow varieties can be seen. The so-called stepped twin planes; HTML, 24 Kb, 2008-07-20 13:04:56; /chapters/glossary/inclusion-in-chrysoberyl.html
296. Incandescence: The emission of light by a substance due to high temperatures: white or bright-red heat. When objects such as iron placed in fire it become dull red by 700 C degree. From 700 C degree to 1500 C degree, the color shifted from red to orange and definitely y; HTML, 25 Kb, 2008-07-20 13:04:54; /chapters/glossary/incandescence.html
297. Inamori synthetic pulled alexandrite: A promotion term for synthetic alexandrite or alexandrite cat's-eye made by Kyocera company, Japan.; HTML, 23 Kb, 2008-07-20 13:04:52; /chapters/glossary/inamori-synthetic-pulled-alexandrite.html
298. Imitation: To result something of a genuine article or natural gemstone or simulate it from any material that imitate by its color, the appearance of a natural gemstone. Imitation gemstone having wholly different physical properties and chemical composition, and hen; HTML, 25 Kb, 2008-07-20 13:04:51; /chapters/glossary/imitation.html
299. Hue: The characteristic color that is determined by its wavelength as red, green, blue, purple, yellow, etc., and excludes white, black, and shades of gray in reference to the visible spectrum of light.; HTML, 24 Kb, 2008-07-20 13:04:47; /chapters/glossary/hue.html
300. Host crystal: A crystal or mineral that contains the inclusions of smaller crystals of different minerals or may be is the same as host mineral.; HTML, 23 Kb, 2008-07-20 13:04:45; /chapters/glossary/host-crystal.html

Page 5 of 9 Back to Top << >>

1 2 3 4 5 6 7 8 9

Switch to preferred accessibility theme:

Increase or decrease the text size:

Keyboard navigation and access keys:

Alexandrite

alexandrite natural of photo stone

Tags