corundum


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Related to corundum: Artificial Corundum

co·run·dum

 (kə-rŭn′dəm)
n.
An extremely hard mineral, aluminum oxide, Al2O3, sometimes containing iron, magnesia, or silica, that occurs in gem varieties such as ruby and sapphire and in a common black, brown, or blue form used chiefly in abrasives.

[Tamil kuruntam.]

corundum

(kəˈrʌndəm)
n
(Minerals) a white, grey, blue, green, red, yellow, or brown mineral, found in metamorphosed shales and limestones, in veins, and in some igneous rocks. It is used as an abrasive and as gemstone; the red variety is ruby, the blue is sapphire. Composition: aluminium oxide. Formula: Al2O3. Crystal structure: hexagonal (rhombohedral)
[C18: from Tamil kuruntam; related to Sanskrit kuruvinda ruby]

co•run•dum

(kəˈrʌn dəm)

n.
a mineral, aluminum oxide, Al2O3, noted for its hardness: transparent varieties, as sapphire and ruby, are used as gems, other varieties as abrasives: often made synthetically.
[1720–30; < Tamil kuruntam; akin to Skt kuruvinda ruby]

co·run·dum

(kə-rŭn′dəm)
An extremely hard mineral composed mainly of aluminum oxide. It occurs in gem varieties such as ruby and sapphire and in a dark-colored variety that is used for polishing and scraping. Corundum is the mineral used to represent a hardness of 9 on the Mohs scale.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.corundum - very hard mineral used as an abrasive
mineral - solid homogeneous inorganic substances occurring in nature having a definite chemical composition
emery - a hard grey-black mineral consisting of corundum and either hematite or magnetite; used as an abrasive (especially as a coating on paper)
alumina, aluminium oxide, aluminum oxide - any of various forms of aluminum oxide occurring naturally as corundum
ruby - a transparent deep red variety of corundum; used as a gemstone and in lasers
sapphire - a precious transparent stone of rich blue corundum valued as a gemstone
Translations

corundum

n (Geol) → Korund m
References in periodicals archive ?
The grindability of Inconel 718 using a corundum and a silicon carbide (SiC) grinding wheel is described in [5].
Kalenborn Abresist lining materials include cast basalt, alumina, zirconium corundum, silicon carbide, chrome carbide, hard alloys, trowelable epoxy, flexible wear resistant piping and combinations of the above.
Red sapphires are better known as rubies - they are both varieties of the mineral corundum.
Corundum [Al.sub.2][O.sub.3]--Canadian Shield--Precambrian Rock--Relic Particles Stream of consciousness connects mind and matter, illustrating a geological dream sequence from the present to an actual finding from the deep past.
Schmeier's product offering includes internal grinding wheels in CBN, silicon carbide, ceramic and corundum in vitrified bond, as well as tools for the super finishing process.
This improvement in the mechanical properties was attributed to the formation of the phases of the ceramic, that is, mullite, cristobalite, and corundum. Figure 5(b) shows the variation of the porosities.
Synthetic Sapphire is aluminum oxide and is also known as Corundum or ?- alumina.
Operationally Gemfields succeeded in its ambition of producing 30 million carats of rough emerald and beryl from Kagem, as guided, and 10.3 million carats of rough ruby and corundum from Montepuez, exceeding guidance.
Increase in density points out the increase in hardness due to the formation of a more crystalline compact material corundum using as abrasive.
The parcel was particularly notable for its content of bicoloured sapphires, and Blauwet's quick visual comparison with the gem corundum from Kenya's Dusi deposit (near Garba Tula; see, e.g., Simonet et al., 2004) indicated that the present material was somewhat different.
The gemstones displayed in the exhibition included Emeralds, Rubies, Peridots, Aquamarines, Topaz, Tourmalines, Corundum, Quartz, Garnets, Bastnaesites, Xenotimes, Sphenes, Amethysts, and Zircons etc.
Exports of Pumice Stone, Emery, Natural Corundum, Natural Garnet and other Natural Abrasives has grew month on month basis by 37.72%.