Granaatsteen: Verskil tussen weergawes

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Lyn 9:
Die argetipiese formule is {{chem|Ca|3|Al|2|(|Si|O|4|)|3}}. Die algemene formule {{chem|X|3|Y|2|(|Z|O|4|)|3}}. Granate is [[silikaat|nesosilikate]] met tetrëdriese {{chem|Si|O|4}}-groepe.
 
Die granaatstruktuur is kubies, maar die eenheidsel is taamlik groot (a is ongeveer 12 A). Die sel bevat 8 formule-eenhede, dws 160 atome in totaal. Die drie soorte atome 24Ca, 16Al en 24Si is in holtes tussen die 96 suurstofatome. Daar is drie verskillende holtes. Die kleinste tetraëdriese holte (Z) word gewoonlik deur Si ingeneem, maar soms deur atome soos Ge of Fe. Die aluminiumholte (Y) is oktaëdries en dit kan deur talle ander elemente vervang word. Die grootste holte (X) is 'n vervormde kubus, hoewel dit soms ook as dodekaëder benoem word- en word in die argetipe deur kalsium ingeneem, maar ook dit kan vervang word. <ref name="Geller">{{webaanhaling|url=http://rruff.info/doclib/zk/vol125/ZK125_1.pdf|titel=Crystal chemistry of the garnets, {{Outeur|S. Geller}} Zeitschrift fUr Kristallographie, 125, bls. 1-47 (1967)}}</ref>
 
{|class="wikitable"
Lyn 28:
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Die grootte van die eenheidsel wissel afhankelik van watter element die drie soorte holtes beset. Die volgende tabel gee 'n idee van die verskeidenheid aan elemente wat 'n granaatstruktuur kan oplever. Hierdie gegewens is gebaseer op ''sintetiese'' granate waarvan vasstaan wat hulle samestelling is. Natuurlike granate kan baie wissel in hulle samestelling. Hulle is gewoonlik [[mengkristalle]]. Chemiese ontleding van 'n bepaalde grossularietkristal het byvoorbeeld die samestelling {Ca<sub>2,84</sub>Mg<sub>0,18</sub>}[Al<sub>1,63</sub>Fe<sub>0,25</sub>Mg<sub>0,11</sub>Ti<sub>0,02</sub>](Si<sub>2,96</sub>Al<sub>0,06</sub>)O<sub>12</sub> opgelewer.<ref name="Geller"/>
 
{|class="wikitable sortable"
|-
!X!!Y!!Z!!a
|-
|{{chem|Ca|2+}}||{{chem|Al|3+}}||{{chem|Si|4+}}||1,1851
|-
|{{chem|Mg|2+}}||{{chem|Al|3+}}||{{chem|Si|4+}}|| 1,1459
|-
|{{chem|Ca|2+}}||{{chem|Sc|3+}}||{{chem|Si|4+}}||1,227
|-
|{{chem|Ca|2+}}||{{chem|V|3+}}||{{chem|Si|4+}}||1,209; 1,2070; 1,2068
|-
|{{chem|Ca|2+}}||{{chem|Cr|3+}}||{{chem|Si|4+}}||1,200; 1,1999
|-
|{{chem|Ca|2+}}||{{chem|Fe|3+}}||{{chem|Si|4+}}||1,2048; 1,2059, 1,2067
|-
|{{chem|Ca|2+}}||{{chem|Ga|3+}}||{{chem|Si|4+}}||1,200|-
|{{chem|Ca|2+}}||{{chem|In|3+}}||{{chem|Si|4+}}||1,235
|-
|{{chem|Mn|2+}}||{{chem|Al|3+}}||{{chem|Si|4+}}||1,1621
|-
|{{chem|Mn|2+}}||{{chem|Fe|3+}}||{{chem|Si|4+}}||1,182
|-
|{{chem|Fe|2+}}||{{chem|Al|3+}}||{{chem|Si|4+}}||1,1526
|-
|{{chem|Co|2+}}||{{chem|Al|3+}}||{{chem|Si|4+}}||1,1471
|-
|{{chem|Cd|2+}}||{{chem|Al|3+}}||{{chem|Si|4+}}||1,182
|-
|{{chem|Cd|2+}}||{{chem|V|3+}}||{{chem|Si|4+}}||1,209
|-
|{{chem|Ca|2+}}||{{chem|Al|3+}}||{{chem|Ge|4+}}||1,212
|-
|{{chem|Ca|2+}}||{{chem|Sc|3+}}||{{chem|Ge|4+}}||1,2504
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|{{chem|Ca|2+}}||{{chem|V|3+}}||{{chem|Ge|4+}}||1,2320
|-
|{{chem|Ca|2+}}||{{chem|Cr|3+}}||{{chem|Ge|4+}}||1,2265; 1,2275
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|{{chem|Ca|2+}}||{{chem|Mn|3+}}||{{chem|Ge|4+}}||1,2325
|-
|{{chem|Ca|2+}}||{{chem|Fe|3+}}||{{chem|Ge|4+}}||1,2320; 1,2312
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|{{chem|Ca|2+}}||{{chem|Ga|3+}}||{{chem|Ge|4+}}||1,2251
|-
|{{chem|Ca|2+}}||{{chem|In|3+}}||{{chem|Ge|4+}}||1,262; 1,259
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|{{chem|Ca|2+}}||{{chem|Rh|3+}}||{{chem|Ge|4+}}||1,235
|-
|{{chem|Ca|2+}}||{{chem|Y|3+}}||{{chem|Ge|4+}}||1,2805
|-
|{{chem|Ca|2+}}||{{chem|Dy|3+}}||{{chem|Ge|4+}}||1,283
|-
|{{chem|Ca|2+}}||{{chem|Ho|3+}}||{{chem|Ge|4+}}||1,281
|-
|{{chem|Ca|2+}}||{{chem|Er|3+}}||{{chem|Ge|4+}}||1,2785
|-
|{{chem|Ca|2+}}||{{chem|Tm|3+}}||{{chem|Ge|4+}}||1,2765
|-
|{{chem|Ca|2+}}||{{chem|Yb|3+}}||{{chem|Ge|4+}}||1,274
|-
|{{chem|Ca|2+}}||{{chem|Lu|3+}}||{{chem|Ge|4+}}||1,273
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|{{chem|Sr|2+}}||{{chem|Sc|3+}}||{{chem|Ge|4+}}||1,2785
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|{{chem|Sr|2+}}||{{chem|In|3+}}||{{chem|Ge|4+}}||1,287; 1,288
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|{{chem|Sr|2+}}||{{chem|Y|3+}}||{{chem|Ge|4+}}||1,3085; 1,3091
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|{{chem|Sr|2+}}||{{chem|Ho|3+}}||{{chem|Ge|4+}}||1,309
|-
|{{chem|Sr|2+}}||{{chem|Er|3+}}||{{chem|Ge|4+}}||1,3065
|-
|{{chem|Sr|2+}}||{{chem|Tm|3+}}||{{chem|Ge|4+}}||1,304
|-
|{{chem|Sr|2+}}||{{chem|Yb|3+}}||{{chem|Ge|4+}}||1,303|-
|{{chem|Sr|2+}}||{{chem|Lu|3+}}||{{chem|Ge|4+}}||1,301
|-
|{{chem|Mn|2+}}||{{chem|Al|3+}}||{{chem|Ge|4+}}||1,1902
|-
|{{chem|Mn|2+}}||{{chem|V|3+}}||{{chem|Ge|4+}}||1,2125; 1,2099
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|{{chem|Mn|2+}}||{{chem|Cr|3+}}||{{chem|Ge|4+}}||1,2027
|-
|{{chem|Mn|2+}}||{{chem|Fe|3+}}||{{chem|Ge|4+}}||1,2087
|-
|{{chem|Mn|2+}}||{{chem|Ga|3+}}||{{chem|Ge|4+}}||1,2043
|-
|{{chem|Cd|2+}}||{{chem|Al|3+}}||{{chem|Ge|4+}}||1,2077
|-
|{{chem|Cd|2+}}||{{chem|Sc|3+}}||{{chem|Ge|4+}}||1,2447
|-
|{{chem|Cd|2+}}||{{chem|V|3+}}||{{chem|Ge|4+}}||1,229
|-
|{{chem|Cd|2+}}||{{chem|Cr|3+}}||{{chem|Ge|4+}}||1,2213
|-
|{{chem|Cd|2+}}||{{chem|Mn|3+}}||{{chem|Ge|4+}}||1,227
|-
|{{chem|Cd|2+}}||{{chem|Fe|3+}}||{{chem|Ge|4+}}||1,2261
|-
|{{chem|Cd|2+}}||{{chem|Ga|3+}}||{{chem|Ge|4+}}||1,2191
|-
|{{chem|Cd|2+}}||{{chem|In|3+}}||{{chem|Ge|4+}}||1,2515
|-
|{{chem|Cd|2+}}||{{chem|Rh|3+}}||{{chem|Ge|4+}}||1,2285
|-
|{{chem|Y|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,2002
|-
|{{chem|Gd|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,2111
|-
|{{chem|Tb|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,2074
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|{{chem|Dy|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,2042
|-
|{{chem|Ho|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,2011
|-
|{{chem|Er|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,1981
|-
|{{chem|Tm|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,1957
|-
|{{chem|Yb|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,2002
|-
|{{chem|Lu|3+}}||{{chem|Al|3+}}||{{chem|Al|3+}}||1,1912
|-
|{{chem|Y|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2376
|-
|{{chem|Sm|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2529
|-
|{{chem|Eu|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2518; 1,2498
|-
|{{chem|Gd|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2475
|-
|{{chem|Tb|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2442
|-
|{{chem|Dy|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2409
|-
|{{chem|Ho|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2377
|-
|{{chem|Er|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2348
|-
|{{chem|Tm|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2002
|-
|{{chem|Yb|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2296
|-
|{{chem|Lu|3+}}||{{chem|Fe|3+}}||{{chem|Fe|3+}}||1,2280
|-
|{{chem|Y|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2275
|-
|{{chem|Pr|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2545
|-
|{{chem|Nd|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2506
|-
|{{chem|Sm|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2433
|-
|{{chem|Eu|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2402
|-
|{{chem|Gd|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2375
|-
|{{chem|Dy|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2307
|-
|{{chem|Er|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2255
|-
|{{chem|Yb|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2202
|-
|{{chem|Lu|3+}}||{{chem|Ga|3+}}||{{chem|Ga|3+}}||1,2185
|}
{{Saadjie}}