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Noun
1. white crystalline mineral consisting of aluminum hydroxide; a constituent of bauxite and a source of alumina
(hypernym) mineral
(substance-holonym) bauxite
(substance-meronym) aluminum hydroxide, aluminium hydroxide, hydrated aluminum oxide, hydrated aluminium oxide

nf. gibbsite, white crystalline mineral consisting of aluminum hydroxide

(n.)
A hydrate of alumina.
  

General Information:
 Chemical Formula:
Al(OH)3
 Composition:
(Molecular Weight = 78.00 gm)
Aluminum 34.59 % Al
Hydrogen 3.88 % H 
Oxygen 61.53 % O 
 Empirical Formula:
Al(OH)3
 Environment:
Lateritic soils developed on alunimous rocks in areas of high rainfall.
 IMA Status:
Approved IMA 1960
 Locality:
Bauxite deposits of Arkansas, USA.
 Name Origin:
Named after the American collector, G. Gibbs (1776-1833).
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
bluish, green, green white, gray, or gray white.
 Density:
2.3 - 2.4, Average = 2.34
 Diaphaniety:
Translucent to transparent
 Habits:
Spherical - Spherical, rounded aggregates., Stalactitic - Shaped like pendant columns as stalactites or stalagmites (e.g. calcite)., Earthy - Dull, clay-like texture with no visible c rystalline affinities, (e.g. howlite).
 Hardness:
2.5-3 - Finger Nail-Calcite
 Luminescence:
None.
 Luster:
Vitreous - Pearly
 Streak:
white
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