29:
476:
143:
776:
F. Aguilar, H. Autrup, S. Barlow, L. Castle, R. Crebelli, W. Dekant, K.-H. Engel, N. Gontard, D. Gott, S. Grilli, R. Gürtler, J.-C. Larsen, C. Leclercq, J.-C. Leblanc, F.-X. Malcata, W. Mennes, M.-R. Milana, I. Pratt, I. Rietjens, P. Tobback, F. Toldrá. (2008).
405:
of alkali feldspar stable at yet higher temperature. Microcline may be clear, white, pale-yellow, brick-red, or green; it is generally characterized by cross-hatch twinning that forms as a result of the transformation of
534:
In 2008, it (along with other
Aluminum compounds) was the subject of a Scientific Opinion of the Panel on Food Additives, Flavourings, Processing Aids and Food Contact Materials from the EFSA.
173:
Has perfect cleavage parallel to {001} and good cleavage on {010}. Cleavages intersect at 90°41'. It can be difficult to see cleavage in thin section due to microcline's low relief.
310:
Gridiron twinning distinguishes microcline from other feldspars. Distinguishable from plagioclase because the lamellae in plagioclase are continuous and do not "pinch and swell."
828:
779:"Safety of aluminium from dietary intake[1] – Scientific Opinion of the Panel on Food Additives, Flavourings, Processing Aids and Food Contact Materials (AFC)"
748:
685:
511:
Microcline is exceptionally active ice-nucleating agent in the atmosphere. Recently it has been possible to understand how water binds to the microcline surface.
763:"Call for technical and toxicological data on sodium aluminium silicate (E 554) and potassium aluminium silicate (E 555) authorised as food additives in the EU"
464:. Microcline is identical to orthoclase in many physical properties, and can be distinguished by x-ray or optical examination. When viewed under a
114:
Can be anhedral or euhedral. Grains are commonly elongate with a tabular appearance. May contain lamellae which formed from exsolved albite.
895:
638:
J.D. Atkinson, B.J. Murray, M.T. Woodhouse, T.F. Whale, K.J. Baustian, K.S. Carslaw, S. Dobbie, D. O'Sullivan, T.L. Malkin (2013).
457:
402:
198:
885:
231:
840:
890:
875:
865:
860:
140:, simple twins, or lack twinning altogether. Lamellae in microcline are discontinuous and "pinch and swell".
870:
465:
72:
508:, US and measured ~50 × 36 × 14 m. This could be one of the largest crystals of any material found so far.
441:
crystal system, the prism angle is slightly less than right angles; hence the name "microcline" from the
822:
742:
679:
340:
188:
178:
137:
133:
651:
576:
158:
125:
221:
211:
594:
168:
129:
880:
810:
730:
667:
367:
800:
790:
720:
712:
699:
G. Franceschi, A. Conti, L. Lezuo, R. Abart, F. Mittendorfer, M. Schmid, U. Diebold (2024).
659:
584:
543:
504:
The largest documented single crystals of microcline were found in Devil's Hole Beryl Mine,
469:
259:
241:
154:
119:
51:
501:
explorers who named it apparently confused it with another green mineral from that region.
762:
378:
146:
805:
725:
700:
655:
580:
442:
854:
640:"The importance of feldspar for ice nucleation by mineral dust in mixed-phase clouds"
598:
527:. It was the subject in 2018 of a Call for technical and toxicological data from the
363:
269:
109:
44:
778:
494:
150:
613:
716:
279:
82:
28:
519:
The chemical compound name is potassium aluminium silicate, and it is known as
417:
The chemical compound name is potassium aluminium silicate, and it is known as
639:
461:
434:
407:
394:
104:
White, grey, greyish yellow, yellowish, tan, salmon-pink, bluish green, green.
795:
490:
450:
446:
438:
411:
390:
374:
814:
734:
671:
486:
is either microcline or orthoclase with thin lamellae of exsolved albite.
520:
505:
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453:
418:
398:
289:
663:
589:
564:
475:
386:
370:
142:
845:
132:. This combination leads to a grid pattern, hence microcline displays
382:
493:, is a green variety of microcline. It is not found anywhere in the
498:
474:
528:
472:
which forms a grating-like structure that is unmistakable.
397:; it is more stable at lower temperatures than orthoclase.
264:
nα = 1.514 – 1.529 nβ = 1.518 – 1.533 nγ = 1.521 – 1.539
338:
330:
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21:
381:. Microcline typically contains minor amounts of
701:"How Water Binds to Microcline Feldspar (001)"
8:
827:: CS1 maint: multiple names: authors list (
747:: CS1 maint: multiple names: authors list (
684:: CS1 maint: multiple names: authors list (
437:orthoclase, but because it belongs to the
393:. Microcline forms during slow cooling of
27:
16:Igneous rock-forming tectosilicate mineral
804:
794:
724:
588:
433:Microcline may be chemically the same as
468:, microcline exhibits a minute multiple
141:
555:
274:Up to first order white (roughly 0.007)
820:
740:
677:
18:
705:Journal of Physical Chemistry Letters
445:"small slope". It is a fully ordered
7:
565:"IMA–CNMNC approved mineral symbols"
318:Commonly alters to sericite or clay.
153:of microcline showing crosshatched
14:
302:Inclined extinction to cleavage
1:
717:10.1021/acs.jpclett.3c03235
912:
896:Minerals in space group 2
841:Alkali feldspars U. Texas
26:
765:. EFSA. 7 November 2018.
236:Transparent, translucent
796:10.2903/j.efsa.2008.754
614:"The largest crystals"
612:P.C. Rickwood (1981).
569:Mineralogical Magazine
480:
162:
621:American Mineralogist
478:
466:polarizing microscope
145:
886:Luminescent minerals
479:Feldspar (amazonite)
664:10.1038/nature12278
656:2013Natur.498..355A
590:10.1180/mgm.2021.43
581:2021MinM...85..291W
326:Low negative relief
307:Diagnostic features
136:. Can also display
124:Typically displays
891:E-number additives
876:Triclinic minerals
866:Aluminium minerals
861:Potassium minerals
563:L.N. Warr (2021).
481:
385:. It is common in
362:) is an important
251:Optical properties
163:
130:pericline twinning
650:(7454): 355–358.
489:Amazon stone, or
349:
348:
138:carlsbad twinning
134:gridiron twinning
903:
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635:
629:
628:
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603:
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592:
560:
544:List of minerals
515:As food additive
449:modification of
410:orthoclase into
334:Biaxial negative
260:Refractive index
254:Biaxial negative
242:Specific gravity
203:
155:crystal twinning
90:
57:
56:(repeating unit)
31:
19:
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517:
497:, however. The
431:
379:alkali feldspar
361:
357:
201:
147:Photomicrograph
126:albite twinning
88:
67:
63:
55:
54:
17:
12:
11:
5:
909:
907:
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893:
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883:
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871:Tectosilicates
868:
863:
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768:
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630:
604:
575:(3): 291–320.
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96:Identification
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369:
368:tectosilicate
365:
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270:Birefringence
267:
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110:Crystal habit
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59:
53:
49:
46:
45:Tectosilicate
43:
39:
34:
30:
25:
20:
823:cite journal
786:
783:EFSA Journal
782:
771:
757:
743:cite journal
711:(1): 15–22.
708:
704:
694:
680:cite journal
647:
643:
633:
624:
620:
607:
572:
568:
558:
533:
524:
518:
510:
503:
495:Amazon Basin
488:
482:
432:
422:
416:
414:microcline.
364:igneous rock
351:
350:
331:Optical sign
151:thin section
280:Pleochroism
232:Diaphaneity
83:Space group
855:Categories
789:(7): 754.
627:: 885–907.
550:References
523:reference
462:orthoclase
458:dimorphous
435:monoclinic
421:reference
408:monoclinic
395:orthoclase
391:pegmatites
373:. It is a
352:Microcline
299:Extinction
199:Mohs scale
157:(in cross
73:IMA symbol
22:Microcline
599:235729616
491:amazonite
451:potassium
447:triclinic
439:triclinic
412:triclinic
403:polymorph
375:potassium
366:-forming
345:Colorless
339:Color in
315:Alters to
159:polarized
881:Feldspar
815:37213837
806:10193631
735:38156776
726:10788961
672:23760484
538:See also
521:E number
506:Colorado
484:Perthite
470:twinning
454:feldspar
419:E number
399:Sanidine
290:2V angle
216:Vitreous
202:hardness
189:Tenacity
179:Fracture
169:Cleavage
120:Twinning
41:Category
652:Bibcode
577:Bibcode
499:Spanish
456:and is
429:Geology
387:granite
371:mineral
246:2.5–2.6
193:Brittle
91:(no. 2)
52:Formula
36:General
846:Mindat
813:
803:
733:
723:
670:
644:Nature
597:
383:sodium
377:-rich
354:(KAlSi
323:Relief
294:65–88°
222:Streak
212:Luster
183:Uneven
161:light)
617:(PDF)
595:S2CID
460:with
443:Greek
401:is a
226:White
206:6–6.5
101:Color
60:KAlSi
829:link
811:PMID
749:link
731:PMID
686:link
668:PMID
529:EFSA
525:E555
423:E555
389:and
128:and
801:PMC
791:doi
721:PMC
713:doi
660:doi
648:498
585:doi
341:PPL
284:N/A
149:of
77:Mcc
857::
825:}}
821:{{
809:.
799:.
785:.
781:.
745:}}
741:{{
729:.
719:.
709:15
707:.
703:.
682:}}
678:{{
666:.
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646:.
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625:66
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619:.
593:.
583:.
573:85
571:.
567:.
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425:.
831:)
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793::
787:6
751:)
737:.
715::
688:)
674:.
662::
654::
601:.
587::
579::
360:8
358:O
356:3
89:1
87:P
66:8
64:O
62:3
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