Corundum
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Vocabulary

  • Vernevil Technique- Melt powdered material, then the drops of the melt fall into a growing 'boule' and the crystal is lowered as it grows. The carrot-shaped 'boule is usually several 100 carrot.
  • Abrasive- this term means to use friction & rough textures to smooth and/or clean a surface.
  • Moh's Scale- A scale that is determined by what substance can scratch another, it is also a scale of the hardness of solids, and talc is at 0 and diamond is at 10, being the hardest.
  • Alluvial- A deposit of sand, mud, and other matter formed by flowing water.
  •  Crystalline- formed by crystalization.
  • Taper- to become gradually more slender toward one end.




Facts
  • Primary Origin: Metamorphic and volcanic rock (basalt)
  • Secondary Origin: Alluvial.
  • Another form of Corundum is Emery. It is a mixture of some magnetite, spinel, hematite, and mostly corundum. When emery erodes, it turns into sand that is called “black sand”.
  • Corundum found naturally is usually impure and not found in very big quantities. Corumdum is a very strong, hard, tough, and very stable mineral. Corundum is not affected by acids.
  • The most know forms of Corundum are Sapphires and Rubys.
  • The Chemical form for Corundum is Al2O3. Composition-Aluminum oxide
  • The gravity for it is 3.9-4.1
  • Corundum is a crystalline form of aluminum oxide with hints of iron, titanium, and chromium.
  • Colors of Corundum can be, blue, red, pink, yellow, orange, gray, white, colorless, black, violet
  • The melting point of corundum is about 3711 degrees farenheit.
  • Crystal Habits- include sapphire's typical six-sided barrel shape that may taper into a pyramid, and ruby's hexagonal prisms and blades.
  • Ways to tell if it is Corundum are extreme hardness, density and crystal habit.
  • Cleavage-is absent, although there is parting which occurs in three directions.
  • Luster- Vitreous to adamantine.
  • Fracture- uneven
  • Corundum is the second hardest natural mineral known to science. The hardest mineral, diamond is four times harder than corundum.
  • Moh's Scale Hardness- 9
  • Uses for Corundum are mostly Jewelary (Rubys and Sapphire) and Abrasives.

http://www.minerals.net/mineral/oxides/corundum/corundum.htm
http://www.skywalker.cochise.edu
http://www.geology.com/minerals/corundum
http://nature.berkeley.edu/classes/eps2//wisc/Lect8.html
http://www.galleries.com/minerals/oxides/corundum/corundum.htm
'Title of Strip'
'Title of Strip'

More Facts!!!:)

  • Corundum is also in crystals and masses.
  • The two main colors of corundum are ruby red and sapphire blue!
  • Corundum has many different colors to it, as you can see.
  • Corundum is the second hardest mineral becides a diamond that is four times harder than corundom.
  • It can be found in ignous rocks.
  • Corundom has no cleavage.
  • the Molecular Weight of corundom is 101.96 gm.
  • The chemical symbol for Corundum is Al2O3.
  • Corundum is Transparent to translucent on thin edges
  • Corundum is brittle
  • The streak of corundum is white.
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sites
http://education.yahoo.com/reference/encyclopedia/entry/corundum
http://webmineral.com/data/Corundum.shtml
http://www.minerals.net/mineral/oxides/corundum/corundum.htm