Review of the hydrated oxides of U and Pb, with new X-ray powder data

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1 MINERALOGICAL MAGAZINE, MARCH 1977, VOL. 41, PP Review f the hydrated xides f U and Pb, with new X-ray pwder data MICHEL DELIENS D6partement de G6lgie et de Min6ralgie, Mus6e ryal de l'afrique centrale, 198 Tervuren, Belgium SUMMARY. New X-ray pwderdata are presented fr vandendriesscheite, furmarierite, masuyite, and w61sendrfite. Literature data n the knwn U-Pb hydrated xides is reviewed, and suitable criteria fr their distinctin are set frth. SEVEN hydrated xides f lead and hexavalent uranium are knwn: curite (Schep, I92I), furmarierite (Buttgenbach, I924), masuyite, vandendriesscheite, and richetite (Vaes, 1947), w61sendrfite (Prtas, 1957), and the unnamed 'Mineral C' frm the Wiseman mine, Mitchell Cunty, Nrth Carlina, briefly described by Frndel (1956). ~ The samples in the mineralgical cllectin f the Mus6e ryal de l'afrique centrale frm the uranium depsit f Shinklbwe, Shaba (= Katanga), have been systematically re-examined in rder t select the uranium-lead xides. X-ray diffractin data n the selected specimens have been cmpared with data frm the literature and their qualitative cmpsitins checked; all the abve species except richetite and 'Mineral C' were recgnized. Of the seven species, richetite has never been quantitatively analysed r adequately described, and material fr a new study was nt fund; it shuld be readily distinguished frm the thers, as it ccurs in thin black pseudhexagnal (mnclinic) plates, and the thers are varius shades f range r red. Curite, which is very cmmn at Shinklbwe, is easily distinguished by its acicular habit and its characteristic X-ray pwder pattern (cf. Table V). The present study therefre cncentrated n the fur species vandendriesscheite,furmarierite, masuyite, and wi~lsendrfite; they are all rthrhmbic, with related unit-cell dimensins and similar, thugh distinct, X-ray pwder patterns. They are very similar, t, in habit and physical prperties. Crystals are less than 1, r at mst 2 mm in size, usually tabular n {OOl} with pseudhexagnal utline, and they als ccur as micrcrystalline aggregates r crusts. Such prperties as refractive indices d nt affrd reliable criteria fr differentiating the species-- apart frm the difficulty f determining indices in the range abve 1.8, there are cnsiderable variatins in the values reprted, pssibly due t variatins in the water cntent. The best criterin fr determining these fur minerals is the X-ray pwder pattern. Althugh their patterns display marked similarities, related t their similar pseudhexagnal pseud-cell dimensins (Table u there are several minr but typical differences between them. There is an appreciable decrease in pseud-cell dimensins in the rder vandendriesscheite-furmarieritemasuyite-w61sendrfite, paralleling the decrease in U/Pb rati (Table V). The strng r i 'Mineral X', frm Great Bear Lake, Canada, first described by C. Palache and H. Berman as a U-Pb xide (Am. Mineral. 18, )) and later regarded as UOa. zh~o (C. Palache, ibid. 19, )), has been identified as vandendriesscheite (Frndel, 1956). 9 Cpyright the Mineralgical Sciety.

2 52 M. DELIENS ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ g ~ ~ ~ a ga~ ~ g ~ g ~ 9... e~,, ~.. ~~ ~ ~ 9 G ~. O~ ~ ' 0 O ~ ~l e~ ~ e,l O 0... ~ ~00 ~0 ~ ~ 0 0 0~0~0~000 ~I ~- ~ ~ ~, ~ ~ ~ e~ O~ ko t ~ 0~ 0 ~ ~'~ ~ t.~ I ~.

3 REVIEW OF THE HYDRATED OXIDES OF U AND Pb 53 r~ '-~ "- ~ '.,.- ~ ~ ~ ~ ~ '.,.-,~ ~'~- C ~ ~,m ~ ' ~ 0 ~ ~'~ 0 t~ ~. ~ & ~...~ ~ ~ 0c. ~. g~,~o~,,.....,~.~,,~,~.... ~,~,~ ~ e ~ ~ ~",~..., ~ ~ & ~ ~,~,~ & & && ~, ~,h,= ~ ~& 8 ~ g ~ ~# ~.~,,~ ~ ~ ~~ ~ ~ ~~ d ~'~ ~.~ ~.~ ~ ~ ~ ~ ~ ~~ ~ ~ ~,~~176 ~ ~ ~~~176 ~ ~ ~,.~,~ '~.< u,,~.~.~. u-~ ~ ~-~ ~

4 54 M. DELIENS medium lines 200, 002, and H I (indices fr the Pseud-cell) are particularly useful fr discriminatin, and are listed, tgether with sme ther useful lines, in Table V. Frndel's 'Mineral C' cntains small amunts f many xides ther than lead and uranium, including 2 ~ BaO; hw far these are essential is uncertain. Its refractive index (I.77-I.82) and X-ray pwder pattern (strngest lines 3"46 A 0), 3"9 0), I'916 (6), 2.73 (6)) suggest that it culd pssibly be an impure barian vandendriesscheite, but this is mere speculatin. TABLE III. X-raypwderdatafrmasuyite andfr a syntheticprduct 'apparentdhlamasuyite" (Prtas, I959) Present study Christ and Clark Guillemin Chervet Prtas Frndel (196) (1958) (196) (I959) (1958) RG. 284d RG HM, lo RG Shinklbwe Synthetic Shaba d(a)mes Iris d(a)mes /,:is d(a)mes I hkl d(a) I d(a) I d(a) I d(a) 1 7"IO 80 7'IO 80 7"08 loo 006 7"1 F 7"IO 6"05 I5 6'6 I5 5"99 3f 6'5 5"87 4"6O 4"38 5 4"40 5 4'36 6 4'38 4'30 6 3'88 3f 3' ' "54 3" " " "50 F 3"52 3'48I 80 3" '48 2I "49 3"45 3.I 'I4 3"I '127 Id 3'12 5 ~ "II 2F 3"IO " ,76I I5 2"77 f 2"78 2'6 3 f 2'51 6 I2. O, 12 2" ' ' "6"12 2"48 mf 2"49 2"38 4 2"364 IO 2" " mf 2.28i 30 2" ' f 2"168 IO 2.I68 IO 2.I8 2f 2'I2 4 2"019 4 ~ 2" "008 I O0 2'00 1" " " "95 I7 b 1"936 mf I'853 5b 1'844 2f I'79 4 I~774 lo 1"775 ~ I' I'755 / Ib 1' '739 IO I'74 t 1-74I mf 1"72 4 8"53 2F 7"06 2F 7"10 6"43 f f f 2f 4"56 2f 4"80 2f 4'36 2f 4"35 3"92 F 3"54 F F 3"49 3F F 3F 3'I4 3F 3F 3'09 3F f m 2"78 m m 2'53 rn 3"I5 2"97 2"74 2"51 2'38 IO IOO 20 lo ~ IO "06 IO 1' ' "784 4d I" Vaes 0947) described masuyite as a hydrated xide f Pb and U, but Cuttita (in Frndel, I958) gave the frmula UOa.2H20. A qualitative X-ray flurescence analysis was therefre made f all fur species studied, and cnfirmed the presence f lead in all fur and f calcium in w61sendrfite. In Tables I t IV the new X-ray pwder data (Cu-K~ radiatin, I I4.6 mm diameter camera) are presented and in Table V the unit cell and ptical data fr the fur species are cllected and cmpared with thse f curite, and their distinctive X-ray pwder lines set ut. Discussin Vandendriesscheite. The new X-ray pwder data agree well with thse f Christ and Clark (the latter include many weak lines nt recrded elsewhere, presumably due t lnger expsure),

5 REVIEW OF THE HYDRATED OXIDES OF U AND Pb 55 C ', OOO 2.~-~..~ r-.. "-6 "0 ~ 2 2 ~ O OX ~ >~ c ~',- [--- ~,, ~D L~ <,d'~, ~ 9.'9'9.'9. t,... ~D ~ 0 ~ O~ "0 '~ 0 ~0 ~ ~ 7 ~ ~ ~ ~ Z~ >: ~ ~ - ~. m ~ ~ ~ O~O R -~<,--.t m.< ~~ ~ ~ ~ ~ ~.~.~. ~ ~.- ~ 9. ~ 9 ~~ 0 ChO0 C 0 UD 0 O ~ O0 O O U~O U~ u~o u~ " 0 ~..~.0..n ~ ~ 0~'~ O ~ 0 0 e,i

6 56 M. DELIENS and with Prtas's natural samples. Prtas's synthetic material is als in general agreement, but gave distinctly lwer spacings thrughut. Frndel's data, hwever, include a number f lines nt recrded by ther bservers and ther lines are displaced, while the dubtlet 3'6I, 3'53 A is replaced by a single line at 3'6I r 3"58 A. Furmarierite. The line at 7"24-7"3I A in the present data is prbably nt due t furmarierite itself, but t anther, unidentified mineral present as a pale yellw uter zne n many f the platy crystals; it was nt bserved n ULB B, which des nt give this line, and was nt TABLE V. Summary f data fr the U-Pb xides Vandendriesscheite Furmarierite Masuyite W61sendrfite Curite! 14"7~.* Unit cell 40"85 43"33 Pseud-cell ( 7'04 (a/2) ~rth- I 4"08 (b/l) hexagnal) 7"22 (c/6) Frmula PbO. 7U as. I 2H 20? ( 1"78*; 1"7~ c~ 1.785, 1.79? / 1"85*; 1-81, Refractive t3 { 1-824, 1-84, indices I I"882t, 1"88482 ( 1.86*; 1-82, y { 1"828, 1845, t 1"89?; 1"88482 av~ Med., r > v? ( c, Clurlesst Plechrism {/3 Glden yellw v Glden yellw Orientatin Diagnstic X-ray lines f~ 1[ [OLO17 L/3!1 [loo] /3"6 s 002 ~3"18 vs III 2.80 w 2"42 mw I4'OO A* 41'93 A* 1 I'95 A:~ I I '90 Aw167 16"47 24"22 13"99 t 3"98 14"39 42'6I 7"02 6"85 7" (a/2) 6'99 (a/6) 7'00 6"99 (b/2) 4"12 (b]4) 4"04 (b/6) 3"98 3'97 (a/3) 7"20 (c/2) 7'1 (c/6) 7"02 6'85 PbO.4UOs.4H20* 3PbO.8UOa. IH20[I (Pb, Ca)O.eUOa.2H~O:~ 1-863"; 1"865"I"; I' cd n (OOl)J; x "885"; 1"9}'; I"895"; l'9ot; "II 2" t'89*; 1"94~'; I'915"; I'917"r 2"9 y" n (I):~ 1 "9411 Large, r > vii 50 ~ r > vt -- Clurlessll, ** Pale yellw? -- Pate yellw Deep gld -- Deep yellw Deep gld -- II [IOO]]],** ~ ]l [I~ -- /3 I[ [x] /3 Jl [i1 -- 3"57 vs 002 3"56 m 002 3'46 vs 002 3'51 ms 200 3"52 s IiO 3"IO vs III 3"t6 vs III 3"48 ms 200 6"9 s 6"4 w 3'13 vs Ill 2"73 w 2'51 m 12.5 At 13-i 8'4 2PbO. 5UO3.4HzO ]" 2'05? ; 2"061] 2"07, 2.08"}" ; 2"06, ; 2"I2?~ 2"12~'; z-i511; 2-12tt Large, r > vii v [I fi]ll 3'51 vs ~:]: 3"36 s 3"I1 vs * Christ and Clark, 196. ~: Prtas, 1957, I959. II Larsen and Berman, ** Buttgenbach, I924. :~:~ Bignand, I955. t Frndel, I958. w Prtas in Chervet, Vaes, I947. tt Billiet, I926. w167 Tussaint, I96I. bserved by Christ and Clark, with whse data the present agree well therwise--better than with thse f Prtas. The data f Guillemin differ mainly in the first strng line (7"34 A as against 7' 11-7'2) and the absence f a line at 3"56-3'6 A, which is als absent in the generally line-pr data f Bignand. The data cited by Frndel (I958) fr furmarierite are clearly thse f wslsendrfite, which had nly just been described when his wrk was published. Masuyite. The present data agree well with thse f Christ and Clark and f Chervet. Frndel's data are very different, and his specimen was prbably furmarierite. Guillemin's data are a puzzle: the weak line at 3-88 A suggests furmarierite, but few ther lines fit; the weak line at 2-60 A des nt appear n any ther pattern; many f the ther lines culd equally well be due t masuyite r t w61sendrfite, and material frm the same specimen appears t be w61sendrfite (present study, Table IV). Wdlsendrfite. All the available data are clsely similar, with ne minr discrepancy: a line appears at medium strength at 1-94-I.92 A in sme data and ne at ~' A~in thers, but nly Chervet's Margnac II specimen has bth these lines.

7 REVIEW OF THE HYDRATED OXIDES OF U AND Pb 57 REFERENCES Bignand (C.), Bull. Sc. fr. Mineral. Cristallgr. 78, Buttgenbach (H.), Ann. (Bull.) Sc. gdl. Belgique, 47, C Chervet (J.), I96. Les mindraux uranifkresfrancais; II Les min~raux secndaires. Bibl. Sci. tech. nucl., Presses Universitaires de France (Paris). Christ (C. L.) and Clark (J. R.), I96O. Am. Mineral. 45, IO26-6I. Destas (A.), Guillemin (C.), and Vaes (J. F.), I958. Mindraux d'uranium du Haut-Katanga. Les Amis du Mus6e ryal du Cng belge, Tervuren. Frndel (C.), Am. Mineral. 41,539. U.S. Gel. Surv. Bull Riska (D.), and Frndel (J. W.), U.S. Gel. Surv. Bull A. Guillemin (C.), 1958, in Destas et al., t958. Larsen (E. S.) and Berman (H.), U.S. Gel. Surv. Bull Prtas (J.), C. R. Acad. Sci. Paris, 244, Cntributin ~ l'dtude des xydes d'uranyle hydratds. Th6se, Facult6 des Sciences, Universit6 de Paris. Schep (A.), 192I. C. R. Acad. Sci. Paris, 173, I186. Tussaint (J.), I96I. Ann. Sc. g~l. Belg. 84, 365. Vaes (J. F.), I947. Ann. Sc. gdl. Belg. 70, B [Manuscript received 28 Octber I974, revised 8 May 1976]

THE SEPARATION OF ALUNITE IN ALUNITIC KAOLIN BY SELECTIVE FLOCCULATION

THE SEPARATION OF ALUNITE IN ALUNITIC KAOLIN BY SELECTIVE FLOCCULATION Clays and Clay Minerals, Vl. 23, pp. 468 472. Pergamn Press 1975. Printed in Great Britain THE SEPARATON OF ALUNTE N ALUNTC KAOLN BY SELECTVE FLOCCULATON C. USTAER and. Gi)RGEY Metallurgical Department,