Corresponding twins - Revision history

BrianMcMahon: Tidied translations.

2017-11-09T17:19:16Z

Tidied translations.

BrianMcMahon at 10:49, 13 May 2017

2017-05-13T10:49:25Z

BrianMcMahon: Style edits to align with printed edition

2017-05-13T10:48:52Z

Style edits to align with printed edition

MassimoNespolo at 09:45, 15 May 2006

2006-05-15T09:45:37Z

MassimoNespolo: History

2006-04-26T15:03:53Z

History

MassimoNespolo: /* Definition */ typo

2006-04-26T14:21:21Z

‎Definition: typo

AndreAuthier at 14:19, 26 April 2006

2006-04-26T14:19:26Z

MassimoNespolo at 13:57, 26 April 2006

2006-04-26T13:57:28Z

New page

<font color="blue">Macles correspondantes</font> (''Fr''). <Font color="black">Geminati corrispondenti</Font> (''It'')

In case of [[twinning by merohedry]], when the [[twin element]] is twofold and the crystal is centrosymmetric, the [[twin operation]] can be described either as a rotation or as a reflection (the two operations being equivalent under the action of the center).

In case of [[twinning by pseudomerohedry]], instead, the two twin operations are no longer equivalent even in centrosymmetric crystals but produce different twins, which are called '''reciprocal twins''' (Mügge, 1898) or '''corresponding twins''' (Friedel, 1904, 1926). One of the most classical examples is that of albite vs. pericline twins in feldspars.

Pairs of corresponding twins normally do not have the same frequency of occurrence, as one would be tempted to assume from the identical value of their [[twin obliquity]].

[[Category:Fundamental crystallography]]

← Older revision		Revision as of 17:19, 9 November 2017
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−	<font color="blue">Macles correspondantes</font> (''Fr''). <~~Font~~ color="black">Geminati corrispondenti</~~Font~~> (''It'').	+	<font color="blue">Macles correspondantes</font> (''Fr''). <font color="black">Geminati corrispondenti</font> (''It'').

	== Definition ==		== Definition ==

@@ Line 10: / Line 10: @@
 == History ==
-*Friedel, G. (1904). ''Étude sur les groupements cristallins.'' Extrait du ''Bulletin de la Société de l'Industrie minérale'', Quatrième série, Tomes III et IV. Saint-Étienne, Société de l'imprimerie Thèolier J. Thomas et C., 485 pp.
+*Friedel, G. (1904). ''Étude sur les groupements cristallins.'' Extrait du ''Bulletin de la Société de l'Industrie minérale'', Quatrième série, Tomes III et IV. Saint-Étienne, Société de l'imprimerie Théolier J. Thomas et C., 485 pp.
 *Friedel, G. (1926). ''Leçons de Cristallographie.'' Berger-Levrault, Nancy, Paris, Strasbourg, XIX+602 pp.
 *Mügge, O. (1898). ''Über Translationen und verwandte Erscheinungen in Krystallen. Neues Jahrb. Mineral. Geol. Paläontol.'' '''1''', 71-158.
 [[Category:Twinning]]

@@ Line 1: / Line 1: @@
-<font color="blue">Macles correspondantes</font> (''Fr'').  <Font color="black">Geminati corrispondenti</Font> (''It'')
+<font color="blue">Macles correspondantes</font> (''Fr'').  <Font color="black">Geminati corrispondenti</Font> (''It'').
 == Definition ==
-In case of [[twinning by merohedry]], when the [[twin element]] is twofold and the crystal is centrosymmetric, the [[twin operation]] can be described either as a rotation or as a reflection (the two operations being equivalent under the action of the center).
+In the case of [[twinning by merohedry]], when the [[twin element]] is twofold and the crystal is centrosymmetric, the [[twin operation]] can be described either as a rotation or as a reflection (the two operations being equivalent under the action of the center).
-In case of [[twinning by pseudomerohedry]], instead, the two twin operations are no longer equivalent even in centrosymmetric crystals but produce different twins, which are called '''reciprocal twins''' (Mügge, 1898) or '''corresponding twins''' (Friedel, 1904, 1926). One of the most classical examples is that of albite vs. pericline twins in feldspars.
+In the case of [[twinning by pseudomerohedry]], instead, the two twin operations are no longer equivalent even in centrosymmetric crystals but produce different twins, which are called '''reciprocal twins''' (Mügge, 1898) or '''corresponding twins''' (Friedel, 1904, 1926). One of the most classical examples is that of albite vs pericline twins in feldspars.
 Pairs of corresponding twins normally do not have the same frequency of occurrence, as one would be tempted to assume from the identical value of their [[twin obliquity]].
 == History ==
-*Friedel, G. (1904). Étude sur les groupements cristallins. Extrait du Bullettin de la Société de l'Industrie minérale, Quatrième série, Tomes III e IV. Saint-Étienne, Société de l'imprimerie Thèolier J. Thomas et C., 485 pp.
+*Friedel, G. (1904). ''Étude sur les groupements cristallins.'' Extrait du ''Bulletin de la Société de l'Industrie minérale'', Quatrième série, Tomes III et IV. Saint-Étienne, Société de l'imprimerie Thèolier J. Thomas et C., 485 pp.
-*Friedel, G. (1926). Leçons de Cristallographie. Berger-Levrault, Nancy, Paris, Strasbourg, XIX+602 pp.
+*Friedel, G. (1926). ''Leçons de Cristallographie.'' Berger-Levrault, Nancy, Paris, Strasbourg, XIX+602 pp.
-*Mügge, O. (1898). Über Translationen und verwandte Erscheinungen in Krystallen. Neues Jahrb. Mineral. Geol. Paläontol., 1, 71-158.
+*Mügge, O. (1898). ''Über Translationen und verwandte Erscheinungen in Krystallen. Neues Jahrb. Mineral. Geol. Paläontol.'' '''1''', 71-158.
 [[Category:Twinning]]

← Older revision		Revision as of 09:45, 15 May 2006
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	*Mügge, O. (1898). Über Translationen und verwandte Erscheinungen in Krystallen. Neues Jahrb. Mineral. Geol. Paläontol., 1, 71-158.		*Mügge, O. (1898). Über Translationen und verwandte Erscheinungen in Krystallen. Neues Jahrb. Mineral. Geol. Paläontol., 1, 71-158.

−	[[Category:~~Fundamental crystallography~~]]	+	[[Category:Twinning]]

← Older revision		Revision as of 15:03, 26 April 2006
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	== History ==		== History ==
		+	*Friedel, G. (1904). Étude sur les groupements cristallins. Extrait du Bullettin de la Société de l'Industrie minérale, Quatrième série, Tomes III e IV. Saint-Étienne, Société de l'imprimerie Thèolier J. Thomas et C., 485 pp.
		+	*Friedel, G. (1926). Leçons de Cristallographie. Berger-Levrault, Nancy, Paris, Strasbourg, XIX+602 pp.
		+	*Mügge, O. (1898). Über Translationen und verwandte Erscheinungen in Krystallen. Neues Jahrb. Mineral. Geol. Paläontol., 1, 71-158.

	[[Category:Fundamental crystallography]]		[[Category:Fundamental crystallography]]