603:
591:
29:
614:
731:
An important characteristic of a biaxial material is the angle between the two optic axes, called the optic angle and designated 2V. It is possible to calculate this value from the refractive indices, and also to measure it. For leadhillite both the measured and calculated values of 2V are 10°.
678:
forms also occur. The simplest form with faces parallel to the b axis and cutting the a and c axes (represented as {101}) may develop. When it does it may be striated or curved. The colour is white or pale shades of green, blue or yellow, but the commonest is clear to white. Leadhillite is
732:
When the colour of the incident light is changed the refractive indices change, and so does the value of 2V. This effect is known as dispersion of the optic axes. In leadhillite this effect is strong, with 2V smaller for red light than for violet light (r < v).
725:= 2.01. Compare these values with that for ordinary window glass, which is only 1.5. The refractive index depends upon the direction of travel of light through the crystal. The maximum
1090:
780:. That is, thin shavings can be pared off it. It is heavy, due to the lead content, with specific gravity 6.55, similar to other lead minerals such as
707:
with the optical Z axis parallel to the crystallographic b axis, and the optical X axis inclined to the crystallographic c axis at an angle of −5.5°.
790:
Cleavage is perfect on a plane perpendicular to the c crystal axis. The mineral is usually twinned, according to a variety of twin laws, forming
1139:
555:
Leadhillite belongs to the monoclinic crystal class 2/m, which is the class with the highest symmetry in the monoclinic system. It has a two-fold
1181:
971:
121:
524:
272:
1186:
680:
318:
1176:
583:. There are 8 formula units per unit cell (Z = 8) and the angle β is very nearly equal to 90°. The side-lengths of the
1166:
544:
131:
427:
Galena, calcite and susannite may alter to leadhillite. Leadhillite may alter to cerussite, calcite and susannite
1171:
536:
489:
667:
817:
643:
540:
111:
46:
1161:
262:
252:
1136:
904:
870:
may form pseudomorphs after leadhillite. Heating leadhillite causes it to reversibly transform into
827:
688:
684:
658:
from an adjacent sulfate sheet. The Pb atoms in the sulfate sheets are bonded to 9 or 10 oxygens.
497:
388:
308:
298:
922:
773:
710:
242:
71:
967:
739:
187:
54:
912:
791:
655:
595:
564:
556:
505:
493:
346:
328:
232:
78:
1080:
1143:
729:δ is the difference between the highest and the lowest values. For leadhillite δ = 0.140.
908:
691:, pearly on faces parallel to the plane containing the a and b axes. Tabular forms of
535:(these three minerals have the same formula, but different structures). Leadhillite is
141:
1155:
1085:
926:
751:
726:
704:
675:
671:
532:
501:
368:
222:
153:
638:
groups, and these are arranged in separate sheets. Pairs of carbonate sheets 8(PbCO
496:. It forms transparent to translucent variably coloured crystals with an adamantine
1031:
855:
851:
805:
735:
560:
401:
204:
794:. The typical habit is platy or tabular pseudohexagonal cyclic twinned crystals.
613:
602:
590:
28:
642:) alternate with pairs of sulfate sheets 8. The carbonate sheets virtually have
797:
580:
568:
516:
398:
171:
1107:
Giuseppetti, Mazzi, and Tadini (1990) The crystal structure of leadhillite, Pb
843:
576:
411:
162:
146:
871:
867:
839:
835:
831:
821:
785:
781:
777:
692:
631:
584:
528:
512:
465:
461:
458:
227:
Usually pseudo-hexagonal, thin to thick tabular {001} with hexagonal outline
50:
42:
847:
618:
520:
378:
1094:. Vol. 16 (11th ed.). Cambridge University Press. p. 320.
917:
892:
863:
769:
635:
455:
1063:
1009:
859:
651:
607:
38:
666:
Crystals are usually small to microscopic, and nearly always pseudo-
1079:
612:
601:
589:
647:
452:
630:
Leadhillite has a layered structure. The mineral contains both
34:
830:
found in the oxidised zone of lead deposits associated with
1127:. Neues Jahrbuch für Mineralogie, Monatshefte, 6:255–268
217:
Colourless to white, grey, yellowish, pale green to blue
650:(Pb) atoms in the carbonate sheets are surrounded by 9
547:. Leadhillite was named in 1832 after the locality.
492:system, but develops pseudo-hexagonal forms due to
439:
431:
423:
410:
397:
387:
377:
367:
345:
337:
327:
317:
307:
297:
271:
261:
251:
241:
231:
221:
213:
203:
198:
186:
170:
152:
140:
130:
120:
110:
77:
67:
62:
33:Thin crystals of transparent leadhillite, inside a
21:
646:symmetry, but the sulfate sheets do not. All the
713:are large, giving the mineral its high lustre, n
511:It was discovered in 1832 in the Susannah Mine,
1064:Leadhillite data in the Handbook of Mineralogy
796:Leadhillite is soluble with effervescence in
772:. It breaks with an irregular to conchoidal
587:are a = 9.11 Å, b = 20.82 Å and c = 11.59 Å.
8:
194:c = 11.59 ; β = 90.46°; Z = 8
1005:
1003:
1001:
999:
916:
1073:
1071:
1027:
1025:
1023:
1021:
1019:
1017:
997:
995:
993:
991:
989:
987:
985:
983:
981:
979:
575:/a, meaning that the two-fold axis is a
563:, and the general form is an open-ended
16:Lead sulfate carbonate hydroxide mineral
958:
956:
883:
792:contact, penetration and lamellar twins
617:Leadhillite from the Beer Cellar Mine,
41:which seems to be partially altered to
1103:
1101:
1059:
954:
952:
950:
948:
946:
944:
942:
940:
938:
936:
18:
1057:
1055:
1053:
1051:
1049:
1047:
1045:
1043:
1041:
1039:
406:Yellowish fluorescence in LW or SW UV
57:, Scotland. Size: 5.3 x 5.1 x 4.4 cm.
7:
893:"IMA–CNMNC approved mineral symbols"
750:Leadhillite is a soft mineral, with
488:. Leadhillite crystallises in the
237:Commonly twinned, twin plane {140}
14:
768:to 3, a little less than that of
654:from carbonate groups and by one
1137:Leadhillite on Mineral Galleries
738:yellowish longwave or shortwave
606:Pale grey-blue leadhillite from
27:
1078:Spencer, Leonard James (1911).
464:mineral, often associated with
1032:Leadhillite data on Webmineral
1:
962:Gaines, R. V., et al. (1997)
866:, and conversely calcite and
687:and a resinous to adamantine
504:of 2.5 and a relatively high
824:, Strathclyde, Scotland, UK.
303:Adamantine, resinous, pearly
1203:
1182:Minerals in space group 14
681:transparent to translucent
674:with a hexagonal outline.
596:Mammoth-Saint Anthony Mine
594:Blue leadhillite from the
579:and the mirror plane is a
500:. It is quite soft with a
323:Transparent to translucent
1010:Leadhillite on Mindat.org
26:
1091:Encyclopædia Britannica
820:is the Susanna Mine at
468:. It has the formula Pb
257:Irregular to conchoidal
966:Eighth edition, Wiley
964:Dana’s New Mineralogy,
897:Mineralogical Magazine
622:
610:
599:
616:
605:
593:
543:and macphersonite is
432:Other characteristics
122:Strunz classification
1187:Luminescent minerals
192:a = 9.11, b = 20.82
1177:Monoclinic minerals
1081:"Leadhillite"
918:10.1180/mgm.2021.43
909:2021MinM...85..291W
891:Warr, L.N. (2021).
776:and it is somewhat
746:Physical properties
559:perpendicular to a
132:Dana classification
1167:Carbonate minerals
1142:2005-10-29 at the
711:refractive indices
699:Optical properties
695:are very similar.
623:
611:
600:
338:Optical properties
72:Carbonate minerals
828:secondary mineral
826:Leadhillite is a
740:ultraviolet light
515:in the county of
508:of 6.26 to 6.55.
446:
445:
166:
55:South Lanarkshire
1194:
1172:Sulfate minerals
1146:
1134:
1128:
1105:
1096:
1095:
1083:
1075:
1066:
1061:
1034:
1029:
1012:
1007:
974:
960:
931:
930:
920:
888:
767:
766:
762:
759:
734:The mineral may
557:axis of symmetry
506:specific gravity
494:crystal twinning
347:Refractive index
329:Specific gravity
292:
291:
287:
284:
277:
247:Perfect on {001}
160:
158:Prismatic (2/m)
84:
83:(repeating unit)
31:
19:
1202:
1201:
1197:
1196:
1195:
1193:
1192:
1191:
1152:
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1150:
1149:
1144:Wayback Machine
1135:
1131:
1126:
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1114:
1110:
1106:
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1062:
1037:
1030:
1015:
1008:
977:
961:
934:
890:
889:
885:
880:
854:. It may form
825:
814:
803:
795:
789:
764:
760:
757:
755:
748:
733:
730:
724:
720:
716:
708:
703:Leadhillite is
701:
683:, with a white
664:
641:
628:
574:
553:
539:, susannite is
487:
483:
479:
475:
471:
435:Not radioactive
419:
362:
358:
354:
289:
285:
282:
280:
275:
193:
181:
159:
106:
102:
98:
94:
90:
82:
81:
58:
17:
12:
11:
5:
1200:
1198:
1190:
1189:
1184:
1179:
1174:
1169:
1164:
1154:
1153:
1148:
1147:
1129:
1124:
1120:
1116:
1112:
1108:
1097:
1086:Chisholm, Hugh
1067:
1035:
1013:
975:
972:978-0471193104
932:
903:(3): 291–320.
882:
881:
879:
876:
813:
810:
801:
747:
744:
722:
718:
714:
700:
697:
663:
660:
639:
627:
624:
598:, Arizona, USA
572:
552:
549:
485:
481:
477:
473:
469:
444:
443:
441:
437:
436:
433:
429:
428:
425:
421:
420:
417:
416:Soluble in HNO
414:
408:
407:
404:
395:
394:
393:Strong, r<v
391:
385:
384:
381:
375:
374:
371:
365:
364:
360:
356:
352:
349:
343:
342:
339:
335:
334:
331:
325:
324:
321:
315:
314:
311:
305:
304:
301:
295:
294:
278:
269:
268:
265:
259:
258:
255:
249:
248:
245:
239:
238:
235:
229:
228:
225:
219:
218:
215:
211:
210:
209:1,078.90 g/mol
207:
201:
200:
199:Identification
196:
195:
190:
184:
183:
179:
174:
168:
167:
156:
150:
149:
144:
142:Crystal system
138:
137:
134:
128:
127:
124:
118:
117:
114:
108:
107:
104:
100:
96:
92:
88:
85:
75:
74:
69:
65:
64:
60:
59:
32:
24:
23:
15:
13:
10:
9:
6:
4:
3:
2:
1199:
1188:
1185:
1183:
1180:
1178:
1175:
1173:
1170:
1168:
1165:
1163:
1162:Lead minerals
1160:
1159:
1157:
1145:
1141:
1138:
1133:
1130:
1104:
1102:
1098:
1093:
1092:
1087:
1082:
1074:
1072:
1068:
1065:
1060:
1058:
1056:
1054:
1052:
1050:
1048:
1046:
1044:
1042:
1040:
1036:
1033:
1028:
1026:
1024:
1022:
1020:
1018:
1014:
1011:
1006:
1004:
1002:
1000:
998:
996:
994:
992:
990:
988:
986:
984:
982:
980:
976:
973:
969:
965:
959:
957:
955:
953:
951:
949:
947:
945:
943:
941:
939:
937:
933:
928:
924:
919:
914:
910:
906:
902:
898:
894:
887:
884:
877:
875:
873:
869:
865:
861:
857:
853:
849:
845:
841:
837:
833:
829:
823:
819:
818:type locality
811:
809:
807:
799:
793:
787:
783:
779:
775:
771:
753:
745:
743:
741:
737:
728:
727:birefringence
712:
706:
698:
696:
694:
690:
686:
682:
677:
673:
669:
661:
659:
657:
653:
649:
645:
637:
633:
625:
620:
615:
609:
604:
597:
592:
588:
586:
582:
578:
570:
566:
562:
558:
550:
548:
546:
542:
538:
534:
533:macphersonite
530:
526:
522:
518:
514:
509:
507:
503:
502:Mohs hardness
499:
495:
491:
467:
463:
460:
457:
454:
450:
442:
438:
434:
430:
426:
422:
415:
413:
409:
405:
403:
400:
396:
392:
390:
386:
382:
380:
376:
372:
370:
369:Birefringence
366:
350:
348:
344:
340:
336:
332:
330:
326:
322:
320:
316:
312:
310:
306:
302:
300:
296:
279:
274:
270:
266:
264:
260:
256:
254:
250:
246:
244:
240:
236:
234:
230:
226:
224:
223:Crystal habit
220:
216:
212:
208:
206:
202:
197:
191:
189:
185:
178:
175:
173:
169:
164:
157:
155:
154:Crystal class
151:
148:
145:
143:
139:
135:
133:
129:
125:
123:
119:
115:
113:
109:
86:
80:
76:
73:
70:
66:
61:
56:
52:
48:
47:type locality
44:
40:
36:
30:
25:
20:
1132:
1089:
963:
900:
896:
886:
856:pseudomorphs
852:pyromorphite
815:
806:lead sulfate
749:
721:= 2.00 and n
702:
665:
629:
561:mirror plane
554:
545:orthorhombic
510:
448:
447:
402:fluorescence
205:Formula mass
176:
798:nitric acid
705:biaxial (-)
581:glide plane
569:space group
525:trimorphous
517:Lanarkshire
449:Leadhillite
399:Ultraviolet
341:Biaxial (−)
319:Diaphaneity
172:Space group
45:. From the
22:Leadhillite
1156:Categories
878:References
844:caledonite
812:Occurrence
804:, leaving
784:(6.5) and
662:Appearance
577:screw axis
537:monoclinic
490:monoclinic
440:References
412:Solubility
389:Dispersion
273:Mohs scale
163:H-M symbol
147:Monoclinic
112:IMA symbol
927:235729616
872:susannite
868:cerussite
840:lanarkite
836:anglesite
832:cerussite
822:Leadhills
786:anglesite
782:cerussite
736:fluoresce
717:= 1.87, n
693:susannite
676:Prismatic
668:hexagonal
632:carbonate
626:Structure
585:unit cell
551:Unit cell
529:susannite
513:Leadhills
466:anglesite
462:hydroxide
459:carbonate
424:Alters to
359:= 2.00, n
355:= 1.87, n
188:Unit cell
51:Leadhills
43:cerussite
1140:Archived
848:linarite
774:fracture
752:hardness
670:, being
656:hydroxyl
644:trigonal
619:Missouri
541:trigonal
523:. It is
521:Scotland
379:2V angle
276:hardness
263:Tenacity
253:Fracture
243:Cleavage
233:Twinning
136:17.1.2.1
68:Category
1088:(ed.).
905:Bibcode
864:calcite
778:sectile
770:calcite
763:⁄
672:tabular
652:oxygens
636:sulfate
567:. The
456:sulfate
288:⁄
267:sectile
126:5.BF.40
79:Formula
63:General
970:
925:
860:galena
858:after
788:(6.3).
689:lustre
685:streak
608:Tsumeb
498:lustre
363:= 2.01
309:Streak
299:Lustre
214:Colour
161:(same
39:galena
1084:. In
923:S2CID
754:only
621:, USA
571:is P2
565:prism
527:with
451:is a
373:0.140
313:White
1123:(OH)
1115:)(CO
968:ISBN
850:and
816:The
709:The
648:lead
634:and
531:and
484:(OH)
453:lead
333:6.55
293:to 3
103:(OH)
1111:(SO
913:doi
862:or
800:HNO
476:(CO
383:10°
116:Lhl
95:(CO
37:of
35:vug
1158::
1100:^
1070:^
1038:^
1016:^
978:^
935:^
921:.
911:.
901:85
899:.
895:.
874:.
846:,
842:,
838:,
834:,
808:.
742:.
519:,
472:SO
182:/a
177:P2
91:SO
87:Pb
53:,
49:,
1125:2
1121:2
1119:)
1117:3
1113:4
1109:4
929:.
915::
907::
802:3
765:2
761:1
758:+
756:2
723:γ
719:β
715:α
640:3
573:1
486:2
482:2
480:)
478:3
474:4
470:4
418:3
361:γ
357:β
353:α
351:n
290:2
286:1
283:+
281:2
180:1
165:)
105:2
101:2
99:)
97:3
93:4
89:4
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