Alumina - Revision history

Michel Lamontagne: /* In situ Production */

2021-05-26T03:36:54Z

In situ Production

Michel Lamontagne at 03:13, 26 May 2021

2021-05-26T03:13:23Z

Michel Lamontagne at 03:12, 26 May 2021

2021-05-26T03:12:36Z

Michel Lamontagne at 03:12, 26 May 2021

2021-05-26T03:12:20Z

Michel Lamontagne at 16:48, 11 April 2019

2019-04-11T16:48:58Z

Michel Lamontagne: /* Use */

2019-04-11T16:48:17Z

Use

Jburk at 20:51, 17 December 2018

2018-12-17T20:51:46Z

ChristiaanK: Add image

2013-02-20T17:52:13Z

Add image

Farred: addition

2013-02-19T04:39:07Z

addition

ChristiaanK: Expand

2013-02-16T18:03:04Z

Expand

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 ==[[In-situ resource utilization|In situ Production]]==
 Alumina may be extracted from clays or from minerals such as Feldspar.
 ==Use==

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 '''Alumina''' is the chemical <math>Al_2O_3</math>, or [[aluminium]](III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name="Cairncross">B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium.  Aluminium is the third most common element on Mars after Oxygen and silicon.
 Most aluminium on Mars is not in the form of alumina but rather in the form of alumina-silicates, such as Feldspar.  Aluminium is also a component of volcanic rocks such as basalt.
@@ Line 23: / Line 24: @@
 Alumina is commonly found in clays that were created on Mars as a result of gravity and chemical separation in the primordial oceans.
-== [[In-situ resource utilization|In situ Production]] ==
+==[[In-situ resource utilization|In situ Production]]==
 Alumina may be extracted from clays or from minerals such as Feldspar.

← Older revision		Revision as of 03:12, 26 May 2021
Line 1:		Line 1:
	'''Alumina''' is the chemical <math>Al_2O_3</math>, or [[aluminium]](III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name="Cairncross">B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium. Aluminium is the third most common element on Mars after Oxygen and silicon.		'''Alumina''' is the chemical <math>Al_2O_3</math>, or [[aluminium]](III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name="Cairncross">B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium. Aluminium is the third most common element on Mars after Oxygen and silicon.

		+	__NOTOC__
	Most aluminium on Mars is not in the form of alumina but rather in the form of alumina-silicates, such as Feldspar. Aluminium is also a component of volcanic rocks such as basalt.		Most aluminium on Mars is not in the form of alumina but rather in the form of alumina-silicates, such as Feldspar. Aluminium is also a component of volcanic rocks such as basalt.

@@ Line 6: / Line 6: @@
 ==Characteristics==
-The hardness of corundum by definition 9 on Mohs' scale and it has a white streak and vitreous lustre.<ref name="Cairncross" />. Corundum has a specific gravity between 3.96<ref name="WebsterJobbins">R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref> and 4.1<ref name="Cairncross" />. The different varieties have refractive indices varying from between 1.759 and 1.767 to between 1.770 and 1.779.<ref name="WebsterJobbins">R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref><br />
+The hardness of corundum by definition 9 on Mohs' scale and it has a white streak and vitreous lustre.<ref name="Cairncross" />. Corundum has a specific gravity between 3.96<ref name="WebsterJobbins">R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref> and 4.1<ref name="Cairncross" />. The different varieties have refractive indices varying from between 1.759 and 1.767 to between 1.770 and 1.779.<ref name="WebsterJobbins">R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref><br />Some corundum, including all rubies, display ''asterism'', which is to say that they reflect light in such a way as to form a six-sided star.<ref name="Cairncross" /><ref name="WebsterJobbins" />
 ==Variants==
 The colour of a corundum crystal depends on impurities.
-*Red corundum is known as '''ruby'''.
+*Red corundum is known as '''ruby'''. The red color of Ruby comes from an impurity of considerably less than 1% Chromic oxide.  The chromium is what permits the ruby to be used for a laser, producing red light.  <ref>McGRAW-HILL ENCYCLOPEDIA OF Science & Technology 8th Edition (c) 1997, vol 15, page 688.</ref>
 *Blue corundum is known as '''sapphire'''. It gets its colour from iron and titanium impurities<ref name="Cairncross" />
@@ Line 20: / Line 17: @@
 *Other varieties of corundum crystal are known by ''colour'' sapphire. These are pink, yellow, violet and green sapphire<ref name="Cairncross" />.
-==Occurence==
+==Occurrence==
 On Earth, corundum mainly occurs in [[metamorphic rock]], as well as in [[alluvial deposits]].<ref name="Cairncross" />
 Alumina is commonly found in clays that were created on Mars as a result of gravity and chemical separation in the primordial oceans.
 ==Use==
@@ Line 34: / Line 34: @@
 *Both natural and synthetic corundum is used in jewelry.
 *As a catalyst in the [[Sabatier process]].
 ==References==

← Older revision		Revision as of 16:48, 11 April 2019
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−	'''Alumina''' is the chemical <math>Al_2O_3</math>, or aluminium(III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name="Cairncross">B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium. Aluminium is the third most common element on Mars after Oxygen and silicon.	+	'''Alumina''' is the chemical <math>Al_2O_3</math>, or [[aluminium]](III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name="Cairncross">B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium. Aluminium is the third most common element on Mars after Oxygen and silicon.

	Most aluminium on Mars is not in the form of alumina but rather in the form of alumina-silicates, such as Feldspar. Aluminium is also a component of volcanic rocks such as basalt.		Most aluminium on Mars is not in the form of alumina but rather in the form of alumina-silicates, such as Feldspar. Aluminium is also a component of volcanic rocks such as basalt.

@@ Line 1: / Line 1: @@
-'''Alumina''' is the chemical <math>Al_2O_3</math>, or aluminium(III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name=Cairncross>B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium.
+'''Alumina''' is the chemical <math>Al_2O_3</math>, or aluminium(III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name="Cairncross">B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium.  Aluminium is the third most common element on Mars after Oxygen and silicon.
 [[File:Alumina.jpg||200px|thumb|rigth|Top: a heap of chemically pure [[Activated_(Chemistry)|activated]] alumina. Bottom left: a sapphire. Bottom right: a ruby.]]
 ==Characteristics==
-The hardness of corundum by definition 9 on Mohs' scale and it has a white streak and vitreous lustre.<ref name=Cairncross />. Corundum has a specific gravity between 3.96<ref name=WebsterJobbins>R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref> and 4.1<ref name=Cairncross />. The different varieties have refractive indices varying from between 1.759 and 1.767 to between 1.770 and 1.779.<ref name=WebsterJobbins>R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref><br />
+The hardness of corundum by definition 9 on Mohs' scale and it has a white streak and vitreous lustre.<ref name="Cairncross" />. Corundum has a specific gravity between 3.96<ref name="WebsterJobbins">R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref> and 4.1<ref name="Cairncross" />. The different varieties have refractive indices varying from between 1.759 and 1.767 to between 1.770 and 1.779.<ref name="WebsterJobbins">R. Webster & E.A. Jobbins - ''Gemmologists' compendium'' 7th ed. 2001. ISBN 978-0-7198-0291-1 p. 36.</ref><br />
-Some corundum, including all rubies, display ''asterism'', which is to say that they reflect light in such a way as to form a six-sided star.<ref name=Cairncross /><ref name=WebsterJobbins />
+Some corundum, including all rubies, display ''asterism'', which is to say that they reflect light in such a way as to form a six-sided star.<ref name="Cairncross" /><ref name="WebsterJobbins" />
 ==Variants==
 The colour of a corundum crystal depends on impurities.
-* Red corundum is known as '''ruby'''.
-::The red color of Ruby comes from an impurity of considerabbly less than 1% Chromic oxide.  The chromium is what permits the ruby to be used for a laser, producing red light.  <ref>McGRAW-HILL ENCYCLOPEDIA OF Science & Technology 8th Edition (c) 1997, vol 15, page 688.</ref>
+*Red corundum is known as '''ruby'''.
 * Blue corundum is known as '''sapphire'''. It gets its colour from iron and titanium impurities<ref name=Cairncross />
-* Colourless (pure) corundum is known as '''white sapphire'''.
+::The red color of Ruby comes from an impurity of considerabbly less than 1% Chromic oxide.  The chromium is what permits the ruby to be used for a laser, producing red light.  <ref>McGRAW-HILL ENCYCLOPEDIA OF Science & Technology 8th Edition (c) 1997, vol 15, page 688.</ref>
 * Other varieties of corundum crystal are known by ''colour'' sapphire. These are pink, yellow, violet and green sapphire<ref name=Cairncross />.
 ==Occurence==
-On Earth, corundum mainly occurs in [[metamorphic rock]], as well as in [[alluvial deposits]].<ref name=Cairncross />
+On Earth, corundum mainly occurs in [[metamorphic rock]], as well as in [[alluvial deposits]].<ref name="Cairncross" />
 ==Use==
 * It is used as an [[abrasive]].<ref name=Cairncross />
-* Used in the production of [[refractory]].<ref name=Cairncross />
+*It is used as an [[abrasive]].<ref name="Cairncross" />
-* Ruby [[laser|lasers]] are based around synthetic ruby crystals, portions of which are doped with [[chromium]].
+*Used in the production of [[refractory]].<ref name="Cairncross" />
-* Alumina can be used as an [[aluminium ore]].
+*Alumina in clay is an important component of ceramics., bricks and other building materials.
-* Both natural and synthetic corundum is used in jewelry.
+*Ruby [[laser|lasers]] are based around synthetic ruby crystals, portions of which are doped with [[chromium]].
-* As a catalyst in the [[Sabatier process]].
+*Alumina is the main component of [[aluminium ore]].
 ==Open issues==
 * How common are alumina deposits on Mars?
 ==References==

← Older revision		Revision as of 20:51, 17 December 2018
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	<references />		<references />
−	[[Category:~~Geology~~]]	+	[[Category:Materials]]

← Older revision		Revision as of 17:52, 20 February 2013
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	'''Alumina''' is the chemical <math>Al_2O_3</math>, or aluminium(III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name=Cairncross>B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium.		'''Alumina''' is the chemical <math>Al_2O_3</math>, or aluminium(III) oxide. It occurs naturally as hexagonal crystals called '''corundum''', the second hardest [[mineral]] on Earth.<ref name=Cairncross>B. Cairncross - ''Field guide to rocks and minerals of Southern Africa'' 2004. ISBN 978-1-86872-985-2 pp. 80-82</ref> Used without qualification, '''aluminium oxide''' usually refers to alumina rather than the other oxides of aluminium.
		+
		+	[[File:Alumina.jpg\|\|200px\|thumb\|rigth\|Top: a heap of chemically pure [[Activated_(Chemistry)\|activated]] alumina. Bottom left: a sapphire. Bottom right: a ruby.]]

	==Characteristics==		==Characteristics==