36:
630:
570:
and construction of two 1,500 m (4,900 ft) shafts to reach the 230 feet (70 m) mineral seam was underway in 2015. These will reach a mineable area of around 25,200 hectares (62,000 acres) and
620:
Water treatment additive: Polyhalite can help to remove impurities from water, such as sulfates and chlorides. It can also help to soften water and make it less corrosive.
429:
system, although crystals are very rare. The normal habit is massive to fibrous. It is typically colorless, white to gray, although it may be brick red due to
539:
The only polyhalite mined in the world comes from a layer of rock over 1,000 m (3,300 ft) below North
Yorkshire and extending off the
519:(the naturally occurring form of table salt), their only connection is that both are evaporite minerals. The use of the Greek words for
739:
617:
Soil amendment: Polyhalite can help to improve the drainage and fertility of soil. It can also help to reduce the acidity of soil.
626:
Industrial applications: Polyhale can be used in a variety of industrial applications, such as making glass, soap, and paper.
502:(which comes from the Latin ending -ites, which originally also came from Greek), which is used like the English ending
833:
110:
464:. The only deposit currently being mined lies under North Yorkshire, UK, extending under the adjacent North Sea.
250:
283:
758:
782:"North York Moors potash mine gets £1.7bn go-ahead". The Guardian. 30 June 2015. Retrieved 3 February 2016.
623:
Animal feed additive: Polyhalite can be added to animal feed to improve the nutritional value of the feed.
490:
481:
818:
808:
798:
582:
Polyhalite is used as a fertilizer since it contains four important nutrients and is low in chloride:
813:
803:
100:
169:
240:
230:
664:
453:
743:
8:
273:
263:
668:
823:
682:
567:
216:
686:
201:
Typically fibrous, foliated, massive; rarely as tabular crystals; pseudo-orthorhombic
672:
574:
will be the deepest in Europe. Polyhalite extraction is expected to begin in 2027.
546:
In 2010, the first mining operations of this polyhalite mineral layer commenced at
528:
438:
311:
293:
206:
64:
35:
20:
828:
559:
57:
629:
571:
563:
551:
461:
448:, Austria. It occurs in sedimentary marine evaporites and is a major potassium
444:
Polyhalite was first described in 1818 for specimens from its type locality in
191:
Colorless, white, gray; often salmon-pink to brick-red from included iron oxide
120:
727:
713:
527:
in polyhalite is due to polyhalite consisting of several metals that can form
792:
477:
434:
333:
196:
132:
555:
547:
154:
677:
652:
550:, and the mine is in 2023 the only producer of polyhalite, marketed by
457:
430:
353:
145:
702:
540:
426:
398:
390:
382:
363:
125:
41:
566:
in the area. In March 2020, the
Woodsmith project was taken over by
740:"POLYHALITE | Meaning & Definition for UK English | Lexico.com"
445:
343:
394:
386:
515:
359:
531:
in the more general sense of the word salt used in chemistry.
759:"Banks backstop Sirius Minerals for $ 2.9B UK potash mine"
449:
498:), which mean "many" and "salt", and the German ending
614:Polyhalite has a variety of other uses, including:
543:coast in the UK, deposited 260 million years ago.
506:to form the names of certain chemical compounds.
790:
211:Characteristically polysynthetic on {010}, {100}
460:. It is also present as a 2–3% contaminant of
34:
676:
178:β = 113.94°, γ = 101.15°; Z = 4
698:
696:
628:
509:Despite the similarity in names between
358:Soluble in water, with precipitation of
791:
577:
723:
721:
707:
693:
756:
653:"IMA–CNMNC approved mineral symbols"
650:
441:of 2.8. It is used as a fertilizer.
13:
718:
174:a = 6.95 Å, b = 8.88 Å,
40:Museum specimen of polyhalite and
14:
845:
757:Topf, Andrew (1 September 2016).
425:. Polyhalite crystallizes in the
607:6% MgO as from magnesium sulfate
633:Crystal structure of polyhalite
610:17% CaO as from calcium sulfate
472:The name comes from the German
776:
750:
732:
644:
176:c = 6.95 Å; α = 104.06°,
1:
637:
534:
7:
10:
850:
18:
834:Minerals in space group 2
714:Polyhalite data on Webmin
604:as from sulfate of potash
369:
352:
342:
332:
310:
302:
292:
282:
272:
262:
249:
239:
229:
215:
205:
195:
187:
182:
168:
153:
131:
119:
109:
99:
63:
53:
48:
33:
28:
703:Polyhalite on Mindat.org
562:announced plans for the
476:, which comes from the
467:
728:Handbook of Mineralogy
657:Mineralogical Magazine
634:
632:
433:inclusions. It has a
111:Strunz classification
385:mineral, a hydrated
348:Measured: 60° to 62°
268:Vitreous to resinous
19:For polyhalide, see
746:on October 3, 2016.
678:10.1180/mgm.2021.43
669:2021MinM...85..291W
651:Warr, L.N. (2021).
578:Composition and use
225:}; parting on {010}
16:Sedimentary mineral
819:Triclinic minerals
809:Potassium minerals
799:Magnesium minerals
635:
568:Anglo American plc
303:Optical properties
376:
375:
324:= 1.558 – 1.562 n
320:= 1.546 – 1.548 n
149:
841:
814:Sulfate minerals
804:Calcium minerals
783:
780:
774:
773:
771:
769:
754:
748:
747:
742:. Archived from
736:
730:
725:
716:
711:
705:
700:
691:
690:
680:
648:
603:
592:
492:
483:
439:specific gravity
424:
312:Refractive index
294:Specific gravity
255:
224:
164:
143:
140:
95:
70:
69:(repeating unit)
38:
26:
25:
21:Polyhalogen ions
849:
848:
844:
843:
842:
840:
839:
838:
789:
788:
787:
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781:
777:
767:
765:
755:
751:
738:
737:
733:
726:
719:
712:
708:
701:
694:
649:
645:
640:
601:
597:
591:
587:
580:
560:Sirius Minerals
537:
470:
452:mineral in the
422:
418:
414:
410:
406:
402:
327:
323:
319:
253:
222:
177:
175:
162:
142:
138:
93:
89:
85:
81:
77:
73:
68:
67:
58:Sulfate mineral
44:
24:
17:
12:
11:
5:
847:
837:
836:
831:
826:
821:
816:
811:
806:
801:
785:
784:
775:
749:
731:
717:
706:
692:
663:(3): 291–320.
642:
641:
639:
636:
612:
611:
608:
605:
599:
594:
589:
579:
576:
572:Woodsmith Mine
564:Woodsmith Mine
552:ICL Group Ltd.
536:
533:
469:
466:
462:Himalayan salt
420:
416:
412:
408:
404:
401:with formula:
374:
373:
371:
367:
366:
356:
350:
349:
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237:
236:
233:
227:
226:
221:Perfect on {10
219:
213:
212:
209:
203:
202:
199:
193:
192:
189:
185:
184:
183:Identification
180:
179:
172:
166:
165:
157:
151:
150:
135:
129:
128:
123:
121:Crystal system
117:
116:
113:
107:
106:
103:
97:
96:
91:
87:
83:
79:
75:
71:
61:
60:
55:
51:
50:
46:
45:
39:
31:
30:
15:
9:
6:
4:
3:
2:
846:
835:
832:
830:
827:
825:
822:
820:
817:
815:
812:
810:
807:
805:
802:
800:
797:
796:
794:
779:
764:
760:
753:
745:
741:
735:
729:
724:
722:
715:
710:
704:
699:
697:
688:
684:
679:
674:
670:
666:
662:
658:
654:
647:
643:
631:
627:
624:
621:
618:
615:
609:
606:
595:
585:
584:
583:
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573:
569:
565:
561:
557:
553:
549:
544:
542:
532:
530:
526:
522:
518:
517:
512:
507:
505:
501:
497:
493:
487:
479:
478:Ancient Greek
475:
465:
463:
459:
455:
451:
447:
442:
440:
437:of 3.5 and a
436:
435:Mohs hardness
432:
428:
400:
396:
392:
388:
384:
380:
372:
368:
365:
361:
357:
355:
351:
347:
345:
341:
337:
335:
334:Birefringence
331:
315:
313:
309:
305:
301:
297:
295:
291:
287:
285:
281:
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248:
244:
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220:
218:
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210:
208:
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200:
198:
197:Crystal habit
194:
190:
186:
181:
173:
171:
167:
161:
158:
156:
152:
147:
136:
134:
133:Crystal class
130:
127:
124:
122:
118:
114:
112:
108:
104:
102:
98:
72:
66:
62:
59:
56:
52:
47:
43:
37:
32:
27:
22:
778:
766:. Retrieved
762:
752:
744:the original
734:
709:
660:
656:
646:
625:
622:
619:
616:
613:
581:
556:Polysulphate
545:
538:
524:
520:
514:
510:
508:
503:
499:
495:
489:
485:
473:
471:
456:deposits of
443:
378:
377:
362:and perhaps
159:
137:Pinacoidal (
558:. In 2016,
548:Boulby Mine
306:Biaxial (−)
288:Transparent
284:Diaphaneity
155:Space group
793:Categories
768:1 December
763:mining.com
638:References
593:as sulfate
535:Extraction
511:polyhalite
458:New Mexico
431:iron oxide
379:Polyhalite
370:References
354:Solubility
251:Mohs scale
235:Conchoidal
146:H-M symbol
101:IMA symbol
29:Polyhalite
824:Evaporite
687:235729616
541:North Sea
474:Polyhalit
427:triclinic
399:magnesium
391:potassium
383:evaporite
364:syngenite
338:δ = 0.021
170:Unit cell
126:Triclinic
42:anhydrite
454:Carlsbad
446:Salzburg
419:·2H
344:2V angle
254:hardness
241:Tenacity
231:Fracture
217:Cleavage
207:Twinning
90:·2H
54:Category
665:Bibcode
395:calcium
387:sulfate
328:= 1.567
245:Brittle
115:7.CC.65
65:Formula
49:General
829:Potash
685:
516:halite
488:) and
480:words
381:is an
360:gypsum
274:Streak
264:Luster
144:(same
683:S2CID
529:salts
486:polys
482:πολύς
411:Mg(SO
278:White
188:Color
82:Mg(SO
770:2016
596:14%
586:48%
525:salt
523:and
521:many
513:and
504:-ite
496:hals
468:Name
397:and
298:2.78
105:Plhl
673:doi
554:as
500:-it
491:ἅλς
450:ore
389:of
258:3.5
795::
761:.
720:^
695:^
681:.
671:.
661:85
659:.
655:.
588:SO
407:Ca
393:,
141:)
78:Ca
772:.
689:.
675::
667::
602:O
600:2
598:K
590:3
494:(
484:(
423:O
421:2
417:4
415:)
413:4
409:2
405:2
403:K
326:γ
322:β
318:α
316:n
223:1
163:1
160:F
148:)
139:1
94:O
92:2
88:4
86:)
84:4
80:2
76:2
74:K
23:.
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