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207:). As a crystal grows, new atoms attach easily to the rougher and less stable parts of the surface, but less easily to the flat, stable surfaces. Therefore, the flat surfaces tend to grow larger and smoother, until the whole crystal surface consists of these plane surfaces. (See diagram.)
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typically do not form smooth faces or sharp crystal outlines. As magma cools, the crystals grow and eventually touch each other, preventing crystal faces from forming properly or at all.
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Anhedral crystal growth occurs in a competitive environment with no free space for the formation of crystal faces. An intermediate texture with some crystal face-formation is termed
132:, the presence of euhedral crystals may signify that they formed early in the crystallization of liquid magma or perhaps crystallized in a cavity or
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crystal is growing, new atoms can very easily attach to the parts of the surface with rough atomic-scale structure and many
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meaning a seat or a face of a solid. “Anhedral” derives from the Greek “an”, meaning “not” or “without”.
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composed of mineral grains that have no well-formed crystal faces or cross-section shape in
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crystallize, they do not touch each other. Thus, snowflakes form euhedral, six-sided
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Euhedral crystals have flat faces with sharp angles. The flat faces (also called
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Well-formed crystal with easily recognizable sharp faces (and the opposite term)
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are terms used to describe opposite properties in the formation of
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268:. P. A. Cox. Cambridge: Cambridge University Press. p. 28.
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faces, where new atoms cannot as easily attach themselves.
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140:, or spatial restrictions, from other crystals.
302:Hurlbut, Cornelius S.; Klein, Cornelis (1985).
46:A subhedral sample showing sharp to anhedral
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77:. The opposite is anhedral (also known as
163:Relation of face orientation to structure
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329:Henrich, Victor E.; Cox, P. A. (1996).
262:Henrich, Victor E.; Cox, P. A. (1994).
113:Crystals that grow from cooling liquid
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331:The surface science of metal oxides
265:The surface science of metal oxides
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193:atomic arrangement of the crystal
148:"Euhedral" is derived from the
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310:(20 ed.). Wiley. p.
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65:. Euhedral (also known as
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155:meaning "well, good" and
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251:“an” at etymonline.com
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232:List of rock textures
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306:Manual of Mineralogy
227:Rock microstructure
217:Xenomorph (geology)
199:of relatively low
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16:(Redirected from
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138:steric hindrance
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349:Crystallography
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102:(also known as
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354:Mineral habits
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205:surface energy
177:dangling bonds
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108:hypautomorphic
104:hypidiomorphic
89:microstructure
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222:Crystal habit
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128:crystals. In
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201:Miller index
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93:thin section
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195:: They are
80:xenomorphic
71:automorphic
67:idiomorphic
48:pyrargyrite
343:Categories
295:References
136:, without
122:snowflakes
359:Petrology
144:Etymology
100:subhedral
50:crystals.
34:Euhedral
284:27684864
211:See also
63:crystals
59:anhedral
55:Euhedral
38:crystals
18:Euhedral
126:twinned
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197:planes
189:facets
181:stable
173:halite
157:hedron
36:pyrite
238:Notes
171:As a
150:Greek
130:rocks
120:When
115:magma
75:faces
316:ISBN
280:OCLC
270:ISBN
57:and
134:vug
110:).
106:or
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83:or
69:or
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312:15
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153:eu
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20:)
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