Khinite, Parakhinite, and Dugganite, Three New Tellurates from Tombstone. Arizona

Home , Bromargyrite, Emmonsite, Khinite, Quetzalcoatlite, Rodalquilarite, Xocomecatlite

AmericanMineralogist, Volume 63, pages 1016-10l9, 1978

Khinite,parakhinite, and dugganite, three new tellurates from Tombstone.Arizona

S.A. Wtlt-Ihtts PhelpsDodge Corporation Douglas,Arizona 85607

Abstract

Khinite was found at the Old Guard mine, one pieceknown. It is CurPbTeOn(OH)u, orthorhombic,Fddd, with a : 5.740,b = 9.983,c : 23.960A.Strongest lines are 2.491 (10), 3.451(9),4.866 (8),2.996(7),2.204(7),2.818 (6), 1.916 (6), 1.558 (6). Dark green,H = 3t/2, D calc: 6.69g/cm';a= 2.ll0,F:2.112,y:2.165,2V"= 2go. Two pieces of parakhinite were found at the Emerald mine. Formula also Cu,PbTeOn(OH).,hexagonal P6222 with a = 5.753,c: 17.9584,thus c : %c of khinite. Strongestlines are 3.336 (10), 2.490 (10), 4.800 (8), 1.558 (8), 2.913 (7),2.245 (6),2.994 (5), 1.997(5). Color,H, and D calcare identical to khinite;e : 2.120,o:: 2.155. Several pieces of dugganite were found at three mines. Analysis gave Pb'Zn'(TeOu),(AsOn)r-*(OH).-r,with x :0.94 to 1.33.Hexagonal, perhaps P6/mmm,witha : 8.472,c : 5.208,{;strongest lines are 3.284 (10), 2.997 (8),2.446 (6),1.896 (6), 1.603(6), 2.773(5),1.177 (5), 5.204 (4). Colorless to variousgreens (with CuO : 0-1.5percent), H : 3, G = 6.33,D calc: 6.339/cms;c':: 1.977, c: 1.967. IMA approvalof thesespecies is pending.

Introduction tered debris remaining. One piece was immediately found, the type specimenof khinite. This piececarries Thisstudy began with a visitby R. W. Thomssenin two other new speciesas well. Khinite occurs as the summerof 1977.He brought a spectacularun- corroded, deep green crystals that form rings on frac- known,subsequently identified as rodalquilarite, that ture surfaces.Massive chlorargyrite occupies the cen- he had found on a mine dump at Tombstone. ter of the rings,and khinite showsreplacement on the Spurredon by this discovery,I beganan exhaustive outside by a sparkling druse of minute dugganite searchof all mine dumpsin the district.This very crystals.The matrix is coarseglassy quartz (intensely quicklyyielded more than twentynew tellurium spe- silicified granodiorite). There are a few pockets of ciesas well as rare ones such as sonoraite,quetzal- granular quetzalcoatlitehosting grains of gold, and coatlite,and xocomecatlite. chrysocollaand tenorite staining is common. This is 'tellurium The occurrenceof mineralsat Tomb- the only specimenof khinite known. stonehas long beenknown. Hessite-wasfound in As examinationof dumps in the district continued, early workings,and Tombstoneis the type locality the Emerald mine quickly yielded severalpieces of for emmonsite,first describedby Hillebrand(1885), dugganite with a bewildering variety of other new probablyfrom the samelocality where rodalquilarite tellurates/tellurites.During this time, removal of the occurs.Rasor (1937)noted the occurrenceof em- dump to the leach pad was begun, so efforts were monsite,and discussedtwo unknowntellurites. His redoubled to visit the rapidly vanishing supply as suiteof samples,preserved at the Universityof Ari- often as possible. Several pieces rich in unknowns zona,was kindly loanedfor studyby Dr. John An- were found, including two pieces of massive vein thony. It containsseveral new and rare tellurium qvartz containing parakhinite. The first of these was oxysalts. found by BaSaw Khin, mineralogist for Phelps On a secondvisit to Tombstone,the dumpsof the Dodge Corporation. Old Guardmine were examined. This dumphas been Parakhinite is identical in color to khinite, occur- almostentirely removed for heapleaching, only scat- ring as thin crystalline films of fractures in the quartz 0003-004x/ 7 8 /09 I 0- I 0l 6$02.00 l0l6 WILLI A MS.' KH I NITE, PARAKH I NITE, A N D D UGGAN ITE l0r7 gangue or as tabular hexagonaleuhedra in vugs; crys- a poor cleavage on {1120}. No fluorescencewas tals may attain 0.5mm in largest dimension. Like noted. The specific gravity was determined by Ber- khinite, parakhinite may alter to dugganite. Other man balanceusing 5mg at23oC.It is 6.3340.15. associatedspecies are xocomecatlite, bromargyrite, No crystals were suitable for measurement.They and a host of unknown tellurates/tellurites. are slightly curved, stubby prisms, with a length to Dugganite at both localitiesoccurs in either quartz width ratio near 2: L Thin sectionsshow {0001}and or manganeseoxide gangue.Most of the associated { 1120} dominant with tiny { I l2 I }. speciesare tellurates/telluritesyet to be described. Bromargyrite and chlorargyriteare also common ac- Chemistry cessories.Dugganite was also finally found at a third Khinite shows behavior in reagents that closely locality, the Joe Shaft, in a portion of the dump rich matchesthat of parakhinite. Testing for SOs,Cl, Br, in emmonsiteand rodalquilarite. One specimenwas and I gave no response,but owing to extremepaucity found with minute druses of dugganite, cerussite, of material, and the suspicion that its chemistry emmonsite, and yet two more unknown tellurates/ would be identical to parakhinite, no material was tellurites. sacrificed for spectrographicexamination. Instead, material was submitted directly for analysis,and the Physical properties resultsfor Cu, Pb, and Te6+(see Table lA) appearto Crystals on the khinite specimenreach 0.l5mm in justify this caution. In addition, water was not deter- maximum dimension. They are curved or barrel- mined, but was calculatedon the basisof the average shaped bipyramids bounded by a series of Ihkll ratio obtained for Cu/P6/Te. The low sum reflects forms, but supergene corrosion has etched them the presenceoftraces ofchlorargyrite and quartz, too deeply, rendering measurementimpossible. Crystals small in amount to recoverand weigh as insol. The are brittle, showing a fair cleavageon {001},and the formula is thus Cu'PbTeOo(OH).. Mohs hardnessis 3/2.The color is a lovely dark green Spectrographicanalysis of parakhiniteshowed ma- closeto bottle green (RHS l35A), with a vivid green jor Cu, Pb, and Te, with traces of Ca. Analytical streak. No fluorescencewas observed.There was far methods employed were those used for dugganite, too little material for the Berman balance. and the leading to the results shown in Table lA, or a specificgravity is greatly in excessof Clerici solution. formula Cu'Pb(TeOnXOH).. Determination of Ca Using alcohol and beeswax,Thoulet's method was showed negligible amounts present. Microchemical employed with l78pg of material. Severaltrials in- testing showed no COr, NO2, SOB,or Cl, Br, I. dicated G : 6.5-7.0. Parakhiniteis easilysoluble in cold dilute acidsbut The propertiesof parakhinite are identicalto those describedabove for khinite. An estimateof the spe- Table lA. Chemistry of khinite and parakhinite cific gravity (Thoulet method) using 222p9 is also I 23 45 6.5-7.0. Crystals are brilliant hexagonal tablets or Cu0 33.22 o.\17 32.82 0.412 3\.52 equant prisms that reach 0.2mm in maximum, and Pb0 0.r45 0.143 single crystals occurring as fracture fillings may be 32.\ 3r.9 32.3 considerably larger (0.5mm). One perfect crystal Teo3 24.5 0.139 25.7 0.145 25.4 measured on the two-circle goniometer showed H2o (7.6) (0.42r) 7.8 0.428 7.8 {0001},{1120}, and {ll24l in approximatelyequal 97.7 98.2 I00.0 rank. The color of dugganiteis variable for two reasons. (r) Khinite. cu and Pb on 160u9, Te+5 on 284ug; H20 calculated Crystals in some specimensare rich in inclusionsof from average ratio obtained for other constituents, Low an unknown Cu-tellurate, and this imparts a yellow- sum reflects of quartz green color. Even when perfectlypure, however, the traces and chlorargyrite. color is easilyinfluenced by minor amounts of copper {2) Ratios for Khinite, calculated for H20 in substitution for zinc. The best sample found (and (3) Parakhinite. Cu and Pb on 570ug, T.+6 on 450 and 574ug; used for most analytical work) carriessparkling wa- water by Penfield method on 842!9. Traces of quartz noteo ter green(RHS l32D) crystalsup to 0.3mm in length. as insol.

The streak is white, the luster adamantine, and the Ratios for parakhinite crystals could be mistaken for willemite. The Mohs Theory for CurPbTeol|(0H), hardnessis 3, and crystalsare exceedinglybrittlewith WILLIAMS: KHINITE, PARAKHINITE, AND DUGGANITE

Table lB. Chemistry of dugganite and Te6+.For further discussionof the analytical method,the readeris referredto Williams(1975). t23 q Pbo 55.32 0.248 5\.42 54.52 X-ray study Zno 17.5 I 19.8 19.9 All threespecies provided good singlecrystals for > 0.231 cuo t.2 J Weissenbergand rotationpatterns, and all give ex- TeO, 14.0 0.080 14.3 13.4 cellent,clear powder patterns. The results of thepow-

orro5 I0.4 0.045 9.3 9.9 der studyare shownin Tables2-4. of khinitewas rotated on two axesand H.0 t.5 0.083 2.2 2.3 A fragment yiefdedthe followingcell: a : 5.740(+0.005), b : r00.0 I00.0 I00.0 9.983(+0.009), c : 23.960A(+0.09). The space groupis Fddd.The calculateddensity, based on Z : (l) Averaged for four analyses for Pb, zn, Cu; 3 for Te, and 8, is 6.699/cm',in agreementwith the measuredesti-

2 for As on samples ranging from 889 to 1555!9, reset to mateofG:6.5-7.0.

l00Z to compeniate for insol which averaged 3.532, Water Parakhiniteprovided the followinghexagonal cell: a : 5.753(+0.009), c : 17.958A(+0.092); the space by bnfield method on 11.882m9. group is P6"22or P6n22.Etch testingin l0 percent (2) Rations HCI seemsto confirm this choice.If Z : 3, the (3) Theory for Pb^Zn.Te0, (AsO, ) (0H). Stoa) calculateddensity is 6.699/cm1.The c axisof khinite = (4) Theory' for Pb-zn-(Teo,) (Aso,)^ (0H), ^ with x 0.94. 5 J OX 1l-X O-JX is f that of parakhinite,and thus the cell volumeis $ as large. Dugganiteis also hexagonal,P6/mmm. Single- may coat with PbCl, or Pb(NOr)2if heated,or in crystalwork showeda : 8.472(+0.005), c : 5.208A strongacid. In the closedtube, it fusesreadily to a (+0.005).The cell dimensions were refined from pow- syrupybrown slag(after evolving water). der data. lf Z : l, the calculateddensity is 6.339/ Preliminaryspectrographic analysis of dugganite cm3,in agreementwith the measuredvalue. showedmajor Pb, Zn,Te, and As, withtraces of Cd, Optics Ag, Mo, Cu, and Ca. The Pb, Cu, and Zn were determinedby atomicabsorption prior to analysisof Khinite and parakhiniteresemble one another Te6+by visiblespectroscopy. Arsenate was found by stronglyin thin sectionbut areunlike any other min- UV spectroscopyas AsIr. Subsequent analysis for Ca eralsI haveever seen. Indices for bothwere measured and Cl were run, both constituentsproving to be in whitelight usingS-Se melts that were immediately negligible.Microchemical tests showed traces of CO, uncoveredand checked by the Brewstermethod. Khi- and gavenegative reaction for nitrate,chloride, and nite is biaxial(+) with a measured2V of 20oand sulfate. Subsequentanalysis of one sample by indicesate ot : 2.ll}, P : 2.112,t : 2.165(all Schwartzkopf Microanalytical Laboratories in- dicatedonly tracesof COz. Table 2. X-ray powder data for khinite-CrKd radiation, I l4 mm The resultsof analysisof crystallinedugganite hkl l/lo from the Emeraldmine are shownin TablelB, and est. reas. leadto the formulaPb'Zn'TeOu(AsOTXOH)s. Other \ 5.976 5.990 004 5 1.997 partial analysesperformed on a differentsample from I 4.865 \.872 111 5 I .916 this mine, and from one samplefound at the Joe 5 \.607 4.608 022 tt.225 shaft,however, show some substitution of TeO?-for t \.223 113 1 1.877 9 3.451 3,\52 115 r 1.850 AsO.'-, and the formula is better written 5 3.'t16 3.r r8 026 * I .837 PbrZns(TeOu)"(AsOn)r-,(OH).-r,,with Cu sub- 7 , oo< , ooE 008 2 1.753 stitution for Zn probably quite limited. Analyses 2 2.860 2.858 131 3 1.730 doneto dateshow x variesfrom 0.94to 1.33. 6 2.818 2.820 117 1 1.702 Dugganiteis solublein cold diluteHNO, or HCl, + 2.785 2.791 202 4B 1.650 t 7 iiA t 1AA 133 if more but concentratedacid is used, or heating l0 2.\91 2.496 040 1.558 employed,it coatswith Pb(NOr),or PbClr.Taken to 2.488 220 1.445 ignition,it fusesto a brownslag with difficulty,evolv- 3 2.\66 2.\58 135 ing a whitesublimate of TeO, and AsrOr. I 2.330 2.331 206 7 2.204 2.203 137 All sampleswere of coursechecked for both Tea+ IIILLIAMS: KHINITE, PARAKHINITE, AND DUGGANITE l0l9

+0.004).Pleochroism is in rich yellowishgreen (Z Table 4. X-ray powderdata for dugganite-CrKa radiation,l14 and mm camera : yellow- l/lo d d hkl lllo d Parakhiniteshows identical colors, c.r rich est. meas. calc. est. meas. ish green,e : clearemerald green, with <.r) e. Al- \ 5.204 5.208 001 1.687 thoughpleochroic, the in intensity change of coloris \ 4.233 L '?A r10 1.5\4 perfectly slightin bothspecies. Parakhinite is uniaxial J J. bOO 3.669 200 r.603 't'il (- ) showingno opticallyanomalous behavior. Dis- r0 3.284 3.286 1.569 persionis strong(it was not measured)and indices I 2.997 201 1.530 are€:2.120,ot:2.155. 5 2.773 2.713 120 1.459 In thin section,dugganite resembles hidalgoite \ 2.503 2.50\ 002 1.413 5 2.446 2.448 121 1.387 closelyin overall appearanceand mode of occur- 2.\46 300 rence.Refractive indices are higher,however, and 2.454 102 1.36\ : (10.002), ri3A1 measuredfor theNaD line are@ 1.977 e \ 112 1.321 : 2.215 2.218 1.967.Crystals may showsectoring or zoningfea- 2.214 301 1.303 turesand exhibita small(-)2V, but moreperfectly 4 2.121 2.r18 220 1.279 formed,isolated crystals are usually not sectoredand 202 1.2\2 are perfectlyuniaxial. 4 2.035 2.035 130 1.225 * I .953 1.962 221 1.2O9 Discussion 5 1.895 1.895 l3l 1.177 1.898 All threeminerals are clearly unlike tellurates that \ 1.783 1.783 302 havebeen found previously.Their continuedrarity * 1.73tr 1.735 003 doubtlessis due to severalfactors. All are formed only by severeoxidation in acid waters,and if the of thefirst Te'+ in nature,and developmentof micro- oxidezone is penetratedby evenmildly alkalinewa- analyticaltechniques for Tea+/Te"+ . ters, the effectupon telluratessuch as theseis fatal; Type specimensof parakhiniteand dugganitewill they quickly dissolve.Another reasonfor rarity is be providedthe British Museum(Natural History) that the bonanzaores found at Tombstonewere and the Universityof ArizonaGeological Museum. thosecarrying tellurides, and little materialfound its A fragmentof khinite will be given to the British way to the wastedumps. Museum(N.H.). Thereare about two dozenpieces of Khinite is namedto honor BaSawKhin, longtime dugganitecomprising an estimated50mg, 6 piecesof mineralogistfor PhelpsDodge Corporation,who parakhinitewith perhaps5mg, and two chipsof khi- found the first parakhinite.This latter mineral is nite with, at most, 200p"grcmaining (but clearlyvis- named in allusionto its closerelation to khinite. ible). Dugganiteis to honor MarjorieDuggan, the accom- plishedanalytical chemist, and reflectsher discovery Acknowledgments I want to first thank MarjorieDuggan for hersuperb analytical work. Few chemistsof any stripe could extractsuch good data from suchminute samples. Several of my friendscontributed time Table 3. X-ray powder data for parakhinite-CrKa radiation, I l4 to the searchfor specimens:Betty Williams,John Forrester,Ba- Saw Khin, and Robert Jenkins.I am grateful to 7l Minerals Corporationfor permissionto visit their holdingsand obtainsam- l/lo d d hkl l/lo d meas. ca I c. meas. ples. 5.973 5.986 003 5 1.997 Thesenew speciesand nameshave been submitted to the IMA 2 4.986 4.982 100 5 1.915 for approval. 8 4.800 4.80I l0t 3 1.87\ \.352 \.356 r02 2 1.853 References 2 Rin ? qro 103 4 1.739 3 Hillebrand,W. F. (1885)Emmonsite, a ferrictellurite.Proc. Colo- t0 104 4 r.59r 3.336 3.335 rado Sci.Soc.,2, 20-23. q , qq[ t qq? 006 \ 1.669 Rasor, C. A. (1937)Mineralogy and Petography of the Tombstone 2.913 2.913 105 8 1.558 7 Mining District,Arizona. Ph.D. Thesis,University of Arizona. 2.838 2.840 lll 4 1.438 Williams,S. A. (1975)Xocomecatlite, Cu'TeO(OH)I, and tlalo- + I 2.7\o 2.739 112 12additional cite, Cu,oZn"(TeOs)(TeOr)rCl(OH)zo.27HzO, two new minerals t0 2.\9o 2.491 200 I ines to d=1.2 from Moctezuma,Sonora, M exico.M ineral. M ag.,40, 221 -226. 2.\2\ 2.\22 r14 2,245 2.2\5 I t) Manusuipt receiued,April 10, 1978;accepted z.vto z.vtc il6 for publication,May 5, 1978.