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Corundum

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Geology and occurrence, Synthetic corundum & Overview

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Geology and occurrence

SchistGneissMarblesMetamorphicTerranes
24 related topics

Synthetic corundum

Marc Antoine GaudinAluminaColourantJ. J. EbelmenBoric acid
14 related topics

Overview

CrystallineAluminium oxideIronTitaniumVanadium
26 related topics

Structure and physical properties

R3cHexagonal close packingYoung's modulusGPaBinary
6 related topics

Key facts & relationships

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Alters to
May alter to mica on surfaces causing a decrease in hardness
Category
Oxide mineral – Hematite group
Cleavage
None – parting in 3 directions
Color
Colorless, gray, golden-brown, brown; purple, pink to red, orange, yellow, green, blue, violet; may be color zoned, asteriated mainly grey and brown
Crystal class
Hexagonal scalenohedral (3m) H-M symbol: (3 2/m)
Crystal habit
Steep bipyramidal, tabular, prismatic, rhombohedral crystals, massive or granular

Topics to explore

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Overview

Geology and occurrence

Synthetic corundum

Structure and physical properties

Advanced semantic analysis

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Map overview Semantic statistics

Corundum

Nodes75
Edges74
Triples71
Avg. degree1.97
Density0.026667
Components1

How this topic connects Entity context

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Corundum

Top relations

related to Geology and occurrence · 20
Corundum → Abrasive, Afghanistan, Craigmont, Emery-grade, Greek, Historically, India, It, Naxos, New York, North Carolina, Ontario, Other, Pakistan, Peekskill, Russia, Sri Lanka, The, US, Zimbabwe
related to Synthetic corundum · 13
Corundum → Al, Auguste Verneuil, BaF2, Because, Ebelmen, Freil, Frenic, Frimy, In, It, Marc Antoine Gaudin, The, Verneuil
related to Structure and physical properties · 4
Corundum → It, MPa, R3c, The
Alters to · 1
Corundum → May alter to mica on surfaces causing a decrease in hardness
Category · 1
Corundum → Oxide mineral – Hematite group
Cleavage · 1
Corundum → None – parting in 3 directions
Color · 1
Corundum → Colorless, gray, golden-brown, brown; purple, pink to red, orange, yellow, green, blue, violet; may be color zoned, asteriated mainly grey and brown
Crystal class · 1
Corundum → Hexagonal scalenohedral (3m) H-M symbol: (3 2/m)
Crystal habit · 1
Corundum → Steep bipyramidal, tabular, prismatic, rhombohedral crystals, massive or granular
Crystal system · 1
Corundum → Trigonal

Important terminology Word statistics

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Important terminology

mineral synthetic hardness sapphire aluminium chromium high crystal also gpa ruby transparent hematite structure crystals crystallographic modulus used form type

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
CorundumAlters toMay alter to mica on surfaces causing a decrease in hardness1.00infobox
CorundumCategoryOxide mineral – Hematite group1.00infobox
CorundumCleavageNone – parting in 3 directions1.00infobox
CorundumColorColorless, gray, golden-brown, brown; purple, pink to red, orange, yellow, green, blue, violet; may be color zoned, asteriated mainly grey and brown1.00infobox
CorundumCrystal classHexagonal scalenohedral (3m) H-M symbol: (3 2/m)1.00infobox
CorundumCrystal habitSteep bipyramidal, tabular, prismatic, rhombohedral crystals, massive or granular1.00infobox
CorundumCrystal systemTrigonal1.00infobox
CorundumDana classification4.3.1.11.00infobox
CorundumDiaphaneityTransparent, translucent to opaque1.00infobox
CorundumEmeryBlack granular corundum intimately mixed with magnetite, hematite, or hercynite1.00infobox
CorundumFormulaAl2O31.00infobox
CorundumFractureConchoidal to uneven1.00infobox
CorundumFusibilityInfusible1.00infobox
CorundumIMA symbolCrn1.00infobox
CorundumLusterAdamantine to vitreous1.00infobox
CorundumMelting point2,044 °C (3,711 °F)1.00infobox
CorundumMohs scale hardness9 (defining mineral)1.00infobox
CorundumOptical propertiesUniaxial (−)1.00infobox
CorundumOther characteristicsMay fluoresce or phosphoresce under UV light1.00infobox
CorundumPleochroismNone1.00infobox
CorundumRefractive indexnω = 1.767–1.772 nε = 1.759–1.7631.00infobox
CorundumRubyRed1.00infobox
CorundumSapphireAny color except red1.00infobox
CorundumSolubilityInsoluble1.00infobox
CorundumSpace groupR3c (No. 167)1.00infobox
CorundumSpecific gravity3.95–4.101.00infobox
CorundumStreakColorless1.00infobox
CorundumStrunz classification4.CB.051.00infobox
CorundumTenacityBrittle1.00infobox
CorundumTwinningPolysynthetic twinning common1.00infobox

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