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Additional Studies on Mixed Uranyl Oxide-Hydroxide Hydrate

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Additional Studies on Mixed Uranyl Oxide-Hydroxide Hydrate t45 TheC anadian M brc rala gis t Vol.35, pp. 145-r5r (1997) ADDITIONALSTUDIES ON MIXEDURANYL OXIDE-HYDROXIDE HYDRATE ALTERATIONPRODUCTS OF URANINITEFROM THE PALERMOAND RUGGLESGRANITIC PEGMATITES. GRAFTON COUNTV, NEW HAMPSHIRE EUGENEE. FOORD1 IJ.S. Geolagical Survey, Denver Fedzral Center,.Box 25M6, Mail Stop 905, Dewer, Colarado 80225, U.S-L STANLEYL. KORZEB 13993East Arkona Avmuz, Aurora, CoLorado80012, U.S.A. FREDERICKE. LICHTE U.S.GeoLogical Suney, DenverFederal Cewer,Box 25M6, Mail Snp 973, Denver, Colorado80225, U.SA. JOANJ. FIT?ATRICK U.S.Geolagical Survey, Dmver Fedcral Cewen Box 25M6, Mail Stop912, Denver, Colorado80225, U.SA- ABSTRACT Additional studieson an incompletely characterizedsecondary uranium 'hineral" from the Rugglesand Palermogranitic Fgmatites, New HampshAe,refened to as mineral "A' by Frondel (1956), reveal a mixnre of schoepit€-goupminerals and related nranyl oxide-hydroxide hydrated compounds.A compositechemical analysis yielded (in wt-Vo):PbO 4,85 (EMP), UOa 83.5 (EMP), BaO 0.675 (av. of EMP and ICP), CaO 0.167 (av. of EMP and ICP), KzO 2.455 (av. of EMP and ICP), SrO 021 (ICP), ThO20.85 (CP), HzO 6.9, D9.61. Powder-diffractionX-ray studiesindicaJe a closeresemblance in paffemsbetween mineral "A" atrd severaluranyl oxide-hydroxidehydrated minerals, including the schoepitefamily of mineralsand UOz(OFI)2. The powderdiffraction data for mineral "A" are most similar to those for syntheticUOzrlSHzO and UOz(OII), but other phasesare likely presentas well, TGA analysisof both mineral 'A' and metaschoepiteshow similar weigbt-loss and first derivativecurves. The dominantlosses are at 100'C, with secondaryevents aJ 4{Do and 6@"C. IR spectrashow the prasenceof (OII) andHzO. Uraninite from both pegmatites,analyzed by LAM-ICP-MS, showsthe trresenceof Tlt Pb, K and Ca" Keywords: mineral 'A', uraninite,schoepite, UO2(O[I)2, Rugglas pepatite, Palermopegoarib, New Hampshire. Somaens Des dtudesadditionnelles portant sur un nindral secondaired'rnanium despegnatites granitiques de Rugglaset de Palermq au New Hampshire,dont la caractdrisationdemerne incomplBte [c'est le mineral "A" de Frondel (1956)], monnent qu'il s'agit d'un m6langede min6raux du groupe de la schoepitee1 de compos6soxydes-hydroxydcs hydrat6s d'uranyle. Une analyse chimique compos€ea doon6,en pords,PbO 4.85 (microsonde6lectroniEre, MSE), Uq $.5 (MSE), BaO 0.675 (moyennede MSE et plasmaI couplageinduct'f, PCD, CaO 0.167 (moyennede MSE et PCD, KzO 2.455 (moyennede MSE et PCD, SrO 0.21 (PCD, ThO2 0.85 (PCD, H2O 6.9, >99.61. ks €tudespar difhaction X (m6thode des poudres)r6vdlent une grande ressemblanceentre les spectresdu min6ral 'A" et plusieursoxyde+-hydroxydes hydraf6s d'uranyle, y inclus les min6rauxdu group de la schoepiteet UO2(OI{)2.D'aprds les donn6esde diEfractionX le min€ral "A" ressembledavatrtage aux compos6s synthdtiquesUOz.ee.1.5HzO et UQ(OII)2, nais il est probable que d'autes phasessont aussi impliqu6es. Une analyse thermogravim€triquedu min6ral "A" et tle la m6tashoepitemontrent un taux de perte de poids et une courbedu premier d6riv6 assezsemblables. Les pertesimportantes sont d 100'C, avecdes 6v6nements seconrlaires i 4@oet i 600oC.Le spectreinfra-rouge r6vblela pr6sencede (OII) et de HzO. Des&hantillons d'uraniniteprovenant des deux pegmatiGs, analys6s par PCI avecablation au laser et spectometriede masse,contiennent Tb" Pb, K et Ca (fraduit par la Rddaction) Mots-clds: min6ral "A', uraninite,schoepit€, UO2(OII)2, pegnatite de Ruggles,pgmatite de Palermo,New Hampshire. I E-mail addr"ss: [email protected] 146 INIR,oDUc"iloN other analytical methods,including gas chromato- graphy,X-ray diffraction Q(RD), and transmissionin- An unknownand incompletsly chracterized 3'mhetral" frared spectrophotomety,were utilized during the study o, of wanium was originally describedas phase'A" by of mineral "A uraniniteand schoepite,and tle resul- Frondel (1956) as part of a study on "gummite". Addi- tant data were used to determinethe na.tureof mineral tionalsflrdies wereconductedonmineral "A" in anafiempt "A". IJnsuccassfrrlattempts were made to determine to fully characterizeit asa new species.Uraninite, from unit-cell dimensions from powder-diffraction data four localities, also was chemically studie{ and their using the zone-axismethod of Visser (1969), and to ages determined. Metaschoepitefrom Shinkolobwe, interpret these data by Rietveld structure analysisby Zaire, was chemicallyanalyzed and studiedby thermo- B.C. Chakoumakosatthe OakRidgeNational Laboratory, gravimefiic analysis(TGA). Oak Ridge, Tennessee. Samplesof phase"A" from two bodies of granitic ooA" pegmatite,the PalermoNo. I and Ruggles,were used Tlfi NeruRE oF UNK].IOWN in this investigation.The PalermoNo. 1 pegmatiteis locdted near North Groton Village, Groton, Grafton Mineral "A" is oneof a numberof mineralsid€Nrtind County, New llampshire, andthe Rugglespegmatite is in "gummite" (Frondel 1956).This mineral was found located in Grafton, Grafton County, New Hampshire at six localities, all in granitic pegmatites,at North lseeFig. 1 of Korzeb et al. (1997)1. Wilton, Pale, o, Ruggles,Alst€aq andBeryl Mountairl New Hampshireand at GrassyCreek, Mitchell County, METHoDSor Irrwrsrrcanot North Carolina. We believed it to be a new mineral speciesbased on the X-raypatiems obtained.However, Specimensof phase '4" were obtained from the chemical and structural studreswere not completed. collection of the Harvard University Mineralogical Additional unpubiishedwork was doneon mineral o'A" Museum (HUI4I/Q collection and from Mr. Robert by Frondel (C. Frondel, pers. comnt", 1994 and C.A. Whitnore, Weare,New llampshire.Electron-microprobe, Francis, trErs. comm., 1993). We have attemptedto TGA, (LAM-ICP-MS) laser-ablation microprobe - further clarify the statusof Mineral "A" using maferial inductively coupledplasma - rnassspectometry, and from PalermoNo. 1 mine and Rugglesmine. -.1 -!. j'i. :r::ii -ii! : *.:,i;s; FIc. l. Photographshowing the variable alterationof uraninite to mineral "A". Palermono. l' HtIMlVl# 13205. The width of thefield of view is 1.8cn- PRODUCTS OF ALTERATION OF IJRANINITE 147 oomineral" TADI.B1. CHBMICAL @MPGIr!ON OF MINERAL !A! Mineral "A" is the first to fotm as an FROMTHB PALBRMOMINB GROTON NEW HAMTSHIRE alterationproduct of uraninite(Figs. 1, 2). We alsohave o'mineral'o Elmdc EMP&dCC LA-ICP-MS Co[palte idenffied ttris from several pegnaiites in orldg @lF6 (wr %) a$lysb (wt. A) @lysls (wL %) Maine and Nortl Carolina" and from the Monticello Pb 4J. fluorite disni4 New Mexico. In al1cases, the "minemlo' u 69.tr is a distinctive orangeto yellow-orangecolor. K 0.s Cg 0.0v Resuls of a compositechemical analysis for mineral BA 1.7 ooA" 213 ar€given in Table 1. Additionalanalyocal daJa were s 0.721 providedby TGA for weightloss as a functionof tempera- c 0.07 N 0.01r fire, andby I,AM-ICP-MS formore tlan 70 eleme,lrts. T@l 98.3:t The analyticaldatainTable 1 indicateacomposition Uo3 E5.3 E3.$ very similar to that of two samplesof "gummite" from Tho, 0.85 0.8y Mtchell County,North Carolin4 which yielded X-ray rbo 3.0 4.85, BaO 0.01 0.67f powderpafterns for mineral "A" in Frondel'sstrdy. An ko. 0.07 Yrot o.a averageof the two compositionsafter subtractionfor Cao o.26 0.16?6 uranophaneand FezO:is: BaO 1.6 wt,Vo,PbO8.25Vo, &o 3.n 2.455! SrO 0.21 0217 UOt 8l.5Vo, H2O 8.657o, 2L00J wt.Vo, sro 6.9 6.9 Resultsof aLAM-ICP-MS analysisof mineral "A' Total 100.39 9.@l from the Palermomine are given in Table 2. All of the lead presentis radiogenic,and the 26Pbt2ntPbratio is TGA btal wdgli !c b LmC - 8.i6 wL%, subhadng 186wt% bsue of cwsdcr of UOr b U& betum 80$'md 1@^c qlra h a total of 6J9 0.053,yielding a calculatedage of.329 Mu wt%. Total @b (rufc): 69 wt%r Wts t{tft TGA dtu" 0.72 wl% H There are several significant differences between s&[.|3d b EtzOis 65 wL%, avaluet!@ble ag@twdrEte altoed (EMP) deffiutlodt duab otat Chedol arulyto w@ d@ by a nebo of the electron-microprobe results and the refirodc dsEedcroprobemlysfmU, O, Bq K Pb mdcarc dmby LAM-ICP-MS results.The LAM-ICP-MS showedno KL wsrrdr (U56, Dsru), gsr d'mabgnply aulyo fm ll c, md N, by EMP. The level of Pb dre m arylewedglis 6 1429& dtd,8^a \Wrc*pecdvely,rc dreby cJ. Ba, as opposedta L.2 wt.Vo ed OS6, Rest6r),edlhem![detmhdsr (baat +, md, (CadEalE determined by EMP is greater than that obtained tttntt@) rc dsE by LL ta*m (tls6, Dsvs} I a@ge od 3 by LAM-ICP-MS. On the other hand, K is higher by debi#raffotai, mge of 4 mlyaeE s rcge of 5 mlt8€S I rege of 6 m1,€€4 tEMP; 6rcgeof EMPdtdICFmlte; zICP. LAM-ICP-MS thanbyEMP. - :iq .i.,!?'. i.s! n*h* i fFfu -$ i&s ffi ,;tr .# Frc. 2. Photogra,phshowing a closerview of the variablealteration of uraninite to mineral "A' and relaled secondaryuranium minerals@alermo no. 1). HIIMM# 132005.The width of the field of view is 6 mm. 148 THE CANADIAN MINERALOGIST TAELB 2. POWDM, DIMACTION DATA FOR MINERAL'A' FROM lgE PALERMO AND RUCGLESMINES, MAFTON COTJNTY,NS. Mreral'A" Mhsal'A' Mlneral'A' UO2g'1.5&O p-UOr'2&O Rugglosdm Palernomlne hlermo nine ICDD 2!1,161 ICDD All40l Frodel(1950 (thlsp4er) Powderdffiastomele( de w deI4 IA de d* I/t d& I/I" d& 4 7.U 7.38' 10 ?.E0 t9 7.4 7.n lm 7.53 6.37 7 6.35 6 49 6.n 6.n t0 6.37 5 S.m 2 5.9r . 5 5.32 E 5.09 5.10 2 5.gl x 4.gr 4.70 I 3 4.80 4.n' t 4.49 5 4.26 10 4.26 5 4.V2 I 4.m 3 3.98 3.90 l 9 3.95 3.956 15 3.7t 3.70 30 3.76 4 3.75 3.49 10 3.50 l0 l0 3.528 3.5n lm 3.56 4 3.55 10 t.49 49 3.439 X.431 4 3.4 15 3.376 3.380 50 3.32 7 3.?tt 7 3.n 8l 3.Ut 3.?39 lm 3.n | 3.21 3.lE 7b 3.20 & n 3.92 3.tCl 55 3.11 6 3.16 I 3.(D 3.V2 5 3.04 6 6 3.(b 2 2.vl 6 2.X9 2.W 5 2.%
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