Tnn Americnx Mineralogist of AMERTCA JOTIRNAL of the MTNERAIOGTCAT-Soctety

Tnn AMERIcnx MINERALoGIST oF AMERTCA JOTIRNAL OF THE MTNERAIOGTCAT-SOCTETy

Vol. 55 MAY-JUNE Nos. 5 and 6

KINOITE, A NEW HYDROUS COPPER CALCIUM SILICATE MINERAL FROM ARIZONA of Arizona, Jonu W. ANruoNv, DepartmentoJ Geology,University Tucson,Arizona 85721 AND

Rosrnr B. LaucnoN, I{ ASA, Geology Branch, Monneil Spacecraft Center, Houslon, Teras 77058.

Assrnlcr Kinoite, cuzcarsrsoro.2H2o,a new speciesfrom the northern santa Rita Mountains, Pima county, Arizona, occursas singlecrystals and in veinlets associatedwith apophyllite, native copper, and copper sulfide minerals. It was found in drill coreswhich cut skarn developedin a Paleozoiclimestone sequence. X-ray crystallographicdata include:o:6.990+.004, b:12"89O+ '003,c:5'654* '002 A;F:96'05'+O+t;V:507.@7 At; .puc" group,P21fm.Strongestpowderdiffractionlines are4.72(10),3.052 (8),6.Mr (z),i.io 1+1,s.rss (3),2.9s1 (3), 2.315 (3), and 2.078 Q) L It is monoclinicwith a:b:c:.542:l:,.439, and B:96o95'. Crystalmorphology is domi- presental- nated by lhk\\, ail. crystals are tabular in the b-c plane. {011} is commonly though terminal forms are poorly developed.It exhibits excellent [010] cleavageand distinct [100] and [001] cleavages.It is deepazurite blue and transparentto translucent. Measureddensity is 3.16+.03;the calculatedvalue is 3.193g/cr,rll with Z:2. Hardnessis about 5 on the Mohs scale.crystals are optically(-);2v:68'; a:1.638 (iralegreenish : (a blue),B : 1.665(blue), 7 : 1.676(deep blue). Z /p neatoo, X 6,r distinct' The mineral is named for Fr. EusebioFrancisco Kino (1645-1711),celebrated Jesuit pioneerof the southwesternUnited States.

INrnopucrtoN

Examination of core obtained in exploratory diamond drilling by the Anaconda Company in the Santa Rita Mountains, Pima County, Ari- zona,by Mr. W. F. Mathias, supervising geologist, revealed the presence of a ,,blue oxidized copper mineral" in BX core from depth. The core was subsequently examined by Mr. G. A. Barber, Chief Geologist of the Southwest Region of the Anaconda Company, who observed that although the mineral superficially resembled ^^$ite, it failed to effervesce with dilute HCI. Mr. Barber referred the mineral to one of us (JWA) for identification. The mineral was also subsequently recognized in core from two near-by drill holes, although no more information is available con- cerning its spatial distribution. The type locality is on claims held under 709 7ro IOHN W. ANTHONY AND ROBERT B. LAUGHON

an agreement between the Anaconda Company and the Banner Mining Company, situated on the east side of the northern Santa Rita Moun- tains between the old mining camps of Helvetia, to the northwest, and Rosemont, to the southeast. The locality is 30 airline miles south- southeastfrom Tucson atLat.31o51,N., Long. 110o45rW. The mineral is named in honor of rtalian-born Fr. Eusebio Francisco Kino (1645-1711),the remarkableJesuit missionarywho was for a quar- ter of a century the outstanding figure on the sonora-Arizona-california frontier (Bolton, 1960). Kinoiter (pronounced Kc'no-ite) joins four other copper silicate minerals as having been first recognized from Arizona: shattuckite and bisbeeite (Schaller, 1915), ajoite (Schaller and Vlisidis, 195g), and papagoite (Hutton and Vlisidis, 1960). OccunnBlrcB The core containing the new mineral is from a diamond drill hole which penetrated contact metamorphosed sedimentary rocks consisting prin- cipally of limestones and dolomites corresponding to a paleozoic series exposedat the surface.rn the limited vertical extent of core examined the rock is skarn composedof diopside, garnet, calcite, and quartz. The rock is strongly brecciated and was transected by at least one fault whose gougeconsists of calcite, fine diopside, and an aluminous 15 A expanding- layer smectite. Apophyllite is very abundant in the skarn and occurs characteristically as vuggr, well-crystallized masses as well as along seamsfilling fractures. Kinoite is embeddedin and penetrates the surface of apophyllite crystals. cry'stals of Kinoite in this occurrence are typi. cally well-formed and single. The new mineral is also observed in milli- meter-thick veinlets filling fracture which cut acrossboth skarn and fault gouge. Djurleite, bornite, and chalcopyrite are irregularly disseminated throughout the skarn. Native copper is present in very small amounts in the skarn and is also embeddedin apophyllite crystals with kinoite in the vuggy areas. where the native copper emerges through the surface of apophyllite the portion within the apophyllite is bright while the free portion is tarnished black. Kinoite and native copper are clearly contemporaneouswith apophyllite and are primary in origin, i.e. not formed under oxidizing conditions related to a supergeneprocess. The apophyllite is interpreted as being of a later generation than the skarn minerals and the solutions which gave rise to kinoite and native copper may also have produced the sulfide minerals. l The name kinoite has been approved by the commission on New Mineral Names of the International Mineralogical Association. KINOITE 711

X-nav DrnnnacrtoN SruPv the weissenburg photographs taken about three axial clirectionsshow group rs only systematic omissions to be in 0fr0 with fr: 2n; the space pZr/m.t The unit cell parameters reporterdin Table 1 are the result of averaging least squares refined values obtained from 1) 10 axial reflec- tions measuredwith a single crystal diffractometer, and 2) line measurements on a powder photograph.The powder photograph (Table.2) was Ni- made using a Straumanis-type 114..59mm diameter camera with

t. t-tt at"" aa "*"t o:6.990+.004,4' p meas.:3.16*.03 g/cm8 b:12.890+.0m4 p calc. :3 . 193 g/cm3 c:5.654+.0024 I':507 .09743 6 :96'05'* 04' Z:2 Space Group: P21/rz

indexed fiItered.copper radiation (CuKa:1.541S A;' fne pattern was using the cell parameters obtained from single crystal measurements.

Monpnot,o<;v were Crystals of kinoite are fairly abundant, but no complete euhedra goniom- obtained. Crystal morphology was studied on a Stoe two-circle reflec- eter but becauseof the generally inferior development and poor calcu- tivity of terminal f o.ms the morphological data of Table 3 were lated from the X-ray cell parameiers. Only observedforms are presented cell is in the table. The crystal orientation in agreementwith the X-ray followed for the morphologicaldescription. and are crystals are invariably tabular in the plane of the b and c axes con- slighily elongated by extension on r. The lhk1lzone is striated and of sistently presents a curved aspect becauseof extensive development vicinal forms. on a number of crystals examined these show a tendency arenot toclusterintheregionsot{ttoiana {:zo}. {too} ana {oto} devel= significantly developed on any crystal. Terminal faces are poorly terminal form (Fig. 1). oied but {bf f } i. rhe principal habit-controlling the A pseudoorthorhombic urp..t is imparted' to some specimens by symmetry or...rr.. of lT.tgl which with {ott} suggestsan apparent and inferior quality of plane parall.f to { 1OO} . fhe poor development ihe terminal faces may be the result of solution etching'

analysis of kinoite per- I Centrosymmetry has been confirmed by a cornplete structure 06' formed bv one of us (RBL)' refinement having proceeded to R: 712 JOHN W. ANTEONV AND ROBERT B, LAUGHON

Taer,e 2. X-nav Powonn Du,lnacrron Dara ron KrNonr'

d (meas) (calc)u d lesta d (meas) d (calc)b hkl

15 6.94 6.947 100 rr 2.179 2.179 7t 320 6.M 6.Mr 020 7 2.14 2.147 A 060 6.14 6.115 110 41 2 116 2.117 042 7 5.63 5.612 001 202 A '71 22 2.073 lz.oto 100 4.723 120 742 t9 \z.ozz 4.35 4.345 111 1 r.977 1.976 331 26 3.951 3.957 111 11 1 868 Ir .aoa 312 7 3.741 3.752 12r \r .soo 152 7 J.04) J.OJZ 130 4 1.810 | 8r2 522 +os 121, 11 3.489 [s 4 1.74{J Ir.z+a I l.t 13.474 zffi \r.z:z 400 7 3.412 3.413 031 2 r.708 Ir.too I71 11 3.3M 3.354 2t0 \r.zoo 133 30 3.138 3.rM T31 9 1.681 lt .oss 17r 81 3.052 3.057 220 .oaz 162 7 2.980 \r 2.987 lJl 22 I.628 1.629 342 7 2.920 2.922 140 A 1.610 1.610 080 lz.zoz 221 ( r <,zc IJ 2.799 11 1.570 262 \z.zo+ 041 u.s69 180 I 2.751 12.7s8 211 7 1 502 1.504 342 i2.745 012 6 1.460 [r.+ot 280 7 2.703 2.707 I02 u.461 432 2 ) 6,1) 2.641 r41 A 1.418 1..418 362 tl 2.573 022 48 1.396 r.399 7nn !2.sr: zJl 520 7B 2.505 1.355 1r.:ss 12.513 r02 [1 .3s6 182 lz.4es 122 4 1.339 r.337 r34 [z.soz 244 4 1.321 1.321 124 158 2.353 )2rse 231 2 1.289 r.289 461 i2 .3sl 032 4 L248 1.248 ,t A 12.s4l 122 4 1.208 1.208 2.10.0 30 2.3r5 2.316 300 164 2 2.285 2.290 r l.I/J l1.rI6 132 | 1.176 o64 I 2.236 2.226 301

rntensities estimated visuaily " with calibrated film strip; measured. intensities were compared with intensities obtained on a single crystal difiraclometer to assist in indexing. b only those calculated lines are iisted for whiih there is a match with an observed line.

Puysrcar, aNo Oprrcar pnopBnrrBs KINOITE /IJ

Tasr.B 3. Cnvstn'llocnepnrc Dara ron KrNonn

Kinoite, Monoclinic- 2/ m eib:c: .542i1r.439 p:96"05', rr: 83o55' 1 Poieoiro:.8ll: .437:l rzi!ziqz:2 .288: 1 . 856: : po:6"05' Po': ,816 qn': .439 ro' .I07

P2: B

c 001 90"00' 6005' 83055', 90000' 83055' b 010 000 90 00 000 90"00' 90 00 o 100 90 00 9000 000 90 00 6J JJ nt 110 614l 9000 000 6t 4r 84 39 28 19 n 320 70 t4 9000 000 70L4 84 17 19 46 D 011 t3 39 24 19 83 55 66 25 23 35 84 26 d 10r -90 00 35 18 12518 90 00 41 23 12518 k, tM JJ IJ 28 t6 7246 67 15 25 t2 74 09 * 133 -20 36 2508 99 22 663s 27 49 98 35 is common for the species.The density is 3.16*.03 g,/cm3,the mean of a number of measurementson the Berman density balance of 10 samples rangingin weight from 4 to 47 mg. The calculateddensity is 3.193E/cnlt. The small crystal size precludes satisfactory determination of scratch hardness.Penetration hardnessmeasurements with Knoop and diamond pyramid, indenters were performed by Dr. Walter W. Walker, Depart- ment of Metallurgical Engineering of the University of Arizona' Pene- tration tests were made on embedded crystals using both types of indenters in three orientations: parallel to c and to b, and approximately 45o to these directions. Knoop indentation tests show that the mineral is

Frc. 1. Appearance of typical kinoite crystal JOHN W. ANTHONV AND ROBERT B. LAUGHON

CA7- g"

x. olo

b=X Y. o

Frc. 2. Optical orientation of Kinoite.

harderin the 6 than in the c axial direction.Mohs hardnessvalues equiva- lent.to the Knoop values are2.0 in the 6 and 2.5 in the c direction. (Con_ from 1'_ersign Knoop to Mohs hardnesses follows the work of Hays, Kendall, and Hoskins (1965)). Results of similar penetration tests with the diamond indenter yielded somewhat higher Mohs equivarent hardnessvalues, in the rangefrom 4 to 5. Small specimensize, the problem of correlating penetration hardness values with Mohs scale hardness, and variable behavior related to "low load anomaly" effectscontribute to the uncertainty of the Mohs hardness. The optical orientation of kinoite was determined on the universal stage (Fig. 2). rndices of refraction were measuredin sodium light. The optical data are presented in Table 4. The mineral is strongry pieochroic in blues and blue-greenwith Z>y>X.

Cnnurcar CouposrrroN The results of a chemical analysismad.e on a carefully separatedsample weighing about 45 mg are presentedin Table 3. The analyiis leads to the

t*ottt

a:1.638+0.002 palegreenish blue opt (-) 0:1.665+0.002blue 2tr/(meas.) : 680 t : l. 676+ 0.002deep blue 2V(calc.):640 Z/1c near 0o r (z distinct x:b KINOITE 7ts

Ta.em 5. Cnnurcar, ANnrvsrs oF KrNorrE*

wt.To wt.7a (1) Mole Proportions (2)

CuO 31.10 t.964 27.90 CaO 23.55 2.t09 24.62 Mgo -lJ .019 SiOz 35.90 3 39.58 I{:O 8.16 2.276 7.90

Totai 98.86 100.00

amounts of Ag and Fe' " Emission spectrographic analysis showed trace 1. Herbert M. Ochs, Denver, analYst 2. Theoretical weight percentagesfor CuzCazSisOro'2H:O composition Cur.goCaz.rrMg.ozSirOs.sz'2.28H2O which is in good agreement with the idealized formula confirmed by structure analysisl: cuzcazsiaor0.2H2O. Kinoite is decomposedin dilute HCI with the development of a white residue. Type specimensof kinoite will be deposited with the u.S. National Muszum and the Department of Geology, University ol Arizona'

AcrNowLrocrwNrs brought we are indebted to G. Arthur Barber of the Anaconda company for having Sidney the mineral to our attention and for providing information regarding its occurrence. Hofiman A. Williams kindly verified and corrected the morphological angle table; victor during the made spectrographic and infrared measurements and u.as especially helpful tests. early stages of the study. w. w. walker kindly performed the penetration hardness throughout the we wish to acknowledge the very helpful criticisms of w. John Mclean parameters using work. Dr. Mclean assisted with the determination of the precise ieil crystal- equipment made available through the courtesy of Professor G. A. Jeffrey of the lography Laboratory, University of Pittsburgh.

Rernnr:Ncns

Bor.ron, H. E. (1960) Rim of Cfui,stendozzRussell and Russell, New York' Mohs hard- Hnvs, C., E. G. Krmo.tr,r, aNo C. D. HosrrNs (1965) Correlating Knoop and ness scales.Metd Prog',87' 10G108. mineral from Hurrox, C. O., eNo A. C. Vr-rsrms (1960) Papagoite, a new copper-bearing Ajo, Arizona. Amer. Mineral 45, 599-677. Scnar.r,n*, W. T. (1915) Four new minerals. J. Wash' Acad" Sci' S, 7' copper sili- Scn,tl-mn, W. T., aNo A C. Vr.rsrors (1958) Ajoite, a ner'r'hydrous aluminum cate. Atner. Mi'neral,' 43, t107-tlll.

Manuser'ipt receitted.,October 31, 1969; accepted'for publication, Ianuary 20' 1970'

inde- lThe crystal structure analysis conirms that the Si:O ratio of 3:10 results from pendent SisOrounits within the structure.