KOBEITE FRON,I PARINGA RIVER, SOUTH WESTLAND,NEW ZEALAND

C. OseonNo Huttow, Stanford, (Jniaersity, CaliJornia.

AssrRAct

A tantalum-niobium-titanium-bearing mineral has been found as slender prismatic

crystals in a cobble of graphic granite in gravels of the Paringa River, South Westland,

New Zealand. The mineral is dark brown in color and metamict with the characteristicresinous luster and strikingly conchoidal fracture of a mineral in that physical state. The

refractive index is 2.205 but after being heated to 1200'C. in vacuo a value of 2.35 was re-

corded; specific gravity is close to 5. X-ray difiraction patterns secured from unheated and

carefully heated fragments are either identical to or exhibit insignificant differences from

powder photographs obtained with similarly treated kobeite from the type locality of

Shiraishi, Kyoto Prefecture, Japan. On the basis of these details but in the absence of quan-

titative analytical data, the South Westland mineral is considered to be identical, or very

closely related to, kobeite. The source of the pebble is uncertain but it has probably been

derived from granitic stocks or pegmatites that are known to outcrop in this general area.

OccunnrNcB

The kobeite-bearing cobble, 75 mm. in diameter, was collected whilepanning sands and gravels in the Paringa River, South Westland, NewZealand, at a point approximately f of a mile upstream from the bridgeon the Weheka-Paringa highway. The mineral occurs as very dark brownprismatic crystals that extend intermittently over distances of 30-45mm. with a sheaf-like or radiating arrangement (Figs. 1 and 2) that ratherstrikingly resembles Figs. 1a and 1D in Takubo, Ukai, and Minato's(1950) paper on kobeite. The matrix consists of a coarse aggregate ofoligoclase and microcline with a rude micrographic relationship; veryrare qtrartz, epidote, muscovite, and chlorite complete the mineralassemblage.

Mrwpnalocv

In transmitted light the mineral is deep coffee brown, sometimes semi-opaque, and by reflected light a bright resinous luster and strongly con-choidal fracture surfaces are evident. Crystals are either long prismaticwhen they are clear and transparent, or stumpy and irregular in formwith a tendency to exhibit irregularly distributed areas of much darkerbrown color; these zones may be shown to be much more radioactivethan the more translucent portions of the crystals (Fig.3). This situa-tion is not dissimilar from that found for manganoan allanite fromYosemite National Park (Hutton, 1951, p. 242), and several otherlocalit ies (Marble, 1948, pp. 80-S5). Crystals are coarsely striatedparallel to their lengths and pronounced cross-fracture is evident in thinsection and crushed material.

342

KOBEITE FROM NEW ZEALAND

The mineral is metamict and under strong illumination an almost im-perceptible birefringence may be detected. The refractive index, meas-ured several times in sulfur-selenium glasses, has an average oI 2.205+0.005. After the mineral has been heated at 1200" C. tor 2! hours invacuo the refractive index increases to 2.35+0.01, and at the same timea strong aggregate birefringence becomes evident. The mineral exhibits

Frc. 1. Regularly arranged prismatic crystals of kobeite in a matrix of micrographically

related microcline and oligoclase from Paringa River, South Westland, New Zealand.

Magnification X65.

no superficial alterationl as does Japanese kobeite, but boundary zo\esbetween crystals and enclosing feldspar are very often distinctly stainedbrown, probably as a result of oxidation of iron freed from the mineralduring metamictization. Owing to the limited amount of material avail-able, specific gravity determinations have not been successfully carriedout beyond noting that particles appeared to sink after twelve hourssuspension in a melt of thallous formate and thallous malonatel accord-ingly one may only report that the specific gravity of the Paringa mineralis probably slightly in excess of 5.

I An r-ray powder film of the yellow alteration material that surrounds crystals of

Japanese kobeite indicates that anatase is the chief constituent with line diffuseness that

suggests extremely fine particle size; slightly larger d-spacings than those recorded for pure

anatase (Swanson and Tatge, 1953, p. 46) may be attributed to ionic substitution of Ti4+

ions by the larger Ta5+ and Nb5+ ions. A few additional rather strong lines present are not

attributable to associated minerals.

343

344 C. OSBORNE HUTTON

Fro. 2 (top).Polished surface of micrographic granite that exhibits radiating aggregatesof prismatic crystals of kobeite from Padnga l{iver, South Westland, New Zealand. Dimen-sion from top to bottom of the rock surface is 70 mm.

Ftc. 3 (bottom). Autoradiograph of Paringa River kobeite as exposed on polished sur-face illustrated in Fig. 2. Exposure period was 72 hours.

KOBEITE FROM NEW ZEALAND

Currutcer- C ouposrrroN

It is unfortunate that scarcity of material permitted only qualitativechemical tests to be made. Rare earths, tantalum, niobium, and titaniumwere found to be present in considerable amounts, and the color of theflocculent tannin-complex precipitate devoid of titanium obtained byIeaching potassium bisulphate fusions with 1 per cent tannin solutionin 5/6 HzSOr was reddish-orange in color, a condition that points todominance of niobium over tantalum. The presence of iron, oxidationstate unknown, aluminum, uranium, thorium, and water was verifi.ed,

The Paringa River mineral is apparently insoluble in hot concentratedHCI after long treatment, but some reaction is evident with hot concen-trated HzSOE. It is readily soluble in fused potassium bisulphate. With aconcentrated oxalic acid solution at about 100' C. no noticeable effectwas evident with either the Paringa River mineral or rvith Japanesekobeite. On the other hand, 5 minutes treatment with 1: 1 HF in the coldcaused slight iridescent films to develop on the bright conchoidal fracturesurfaces of the Paringa River mineral, and thin greyish-white opalescentcrusts appeared rather patchily developed on Japanese kobeite. With coldconcentrated HF the effect was only very slightly more evident in eachinstance. In their reactivity towards oxalic acid and HF these two min-erals differ from what is usually found for polycrase-euxenite, eschynite-priorite, fergusonite, or samarskite, since considerable reaction occurswith the latter minerals.

X-Rev Srunv

Powder cameras of 114.59 mm. diameter and nickel-fiItered copperradiation were employed exclusiveiy in this workl and in addition itshould be understood that a single fragment, 0.1-0.2 mm. in diameter,mounted on a glass fiber was used in each instance as the diffractionmaterial rather than powdered specimens.

Pure fragments of the Paringa River mineral and kobeite from Japanhave been subjected to heat-treatment as follows: (1) Samples, in plat-inum microcrucibles, were placed in an already-heated {urnace at 620" C.and at 1200'C.;accordingly these samples were heated in contact withaft. (2) Samples were sealed in Vycor or silica capillaries in vacuo andthen heated at the same temperatures as before, and in addition at900' C. and 1000o C. All samples were r-rayed after having cooled toroom temperature.

Paringa River material untreated in any way, gives weak, usuallydiffuse powder lines (Table 1, column A) after an exposure of 24 hours;this diffraction pattern, which was found to be quite reproducible, ap-pears indicative of remnants of a primitive cubic structure, cell edge

346 C. OSBORNE HUTTON

about 14.3 A, that may have existed before metamictization, and at thesame time the utterly disoriented nature of the mineral is clear. Withmaterial heated in air and in vacuo at 620" C. new patterns are obtainedthat are closely similar to one another, and except for two or three ex-ceedingly faint lines that are not permitted by the space-group, thespacings may be compared to those of a cubic face-centered uraninite-type of pattern with cell edges of 5.029 A and 5.021 A respectively

Terln 1. X-R.qv Drlrnecrrox Plrrnnns Yror,nnn sy UNnrerno FnecunNrs ol rnePanrnca Rrvrn Mrrrnar (,4) aNo Koeurn, Jarar (B)

Radiation CuKa: 1.5418 A. Intensities determined visuailv

d. meas. A d. meas. A

4 . 5 04 . t 63 . 7 53 . 5 0? 7' , '

3 . 2 0

4 .504 . 1 63 . 7 43 .503 .35.t . l.t

2 . 5 52 . 1 82 . 1 0r . 7 4

< 1.)1

< 1< 1

1

<r3I

< 1< 1

1< 1< 1< 1< 1

(Tables 2 and 3). Careful comparison of these films with powder patternsof reverted microlite reveals an absence of several fairly strong lines of theIatter in the former; consequently the patterns of the Paringa Rivermineral are considered to be more comparable to a uraninite--type ratherthan to that of microlite-pyrochlore with cell edges of 10.058 A and 10.042A in which the strongest lines only are developed. It is interesting ronote that heating in contact with air has permitted a slightly largercell to develop; this increase in size is probably due to oxygen intakeduring the heating process.

After being heated in air or in vacuo at 1200" C. fragments of theParinga River material give distinctive r-ray diffraction patterns thatare closely similar to one another (Table 4); particle size has increasedbecause most of the lines are now quite sharp. In each case the threestrongest l ines of the uraninite-type pattern, viz. (111), (200), and (311),persist in the new patterns, although not at the same relative intensities,whereas the strong reflection (220) appears to coincide with or be very

KOBEITE FROM NEW ZEALAND

close to a line that is usually almost imperceptible in the new patterns.Attempts to index these films systematically were unsuccessful and thisfact leads one to the conclusion that two or more phases may be present,although the degree of simplicity in the patterns may be an argument

Tasru 2. X-Rav DrrlnecrroN Pomnn ParrnnNs on PenrNoe Rrl'rn Me-TERTAL AND Korarre, Jeler.l

All samples heated for one hour at 620" C. Radiation CuKa:1.5418 A

d. meas. A a.. .u. . A I I d. meas A d. meas. A I

347

a + . l J

J . / O

2 . 8 92 . 5 0 51 . 7 7 71 . 5 1 61 .4531 . 2 5 5l . l J 4

1 . 1 2 51.028

,969

.851

.838

I

< 110487II1 4

1 4

1 !

1 4L r

<r#a !

4 . 1 53 . 7 42 . 8 92 . 5 0 8I 1 J )

1 . 5 1 3

1 . 2 5 4I - t . ) . t

r . 1 2 41.026

.967

.888

.850

.839

II

10

8711

rlf1 4

) 4

< 1)4

7.4

4 . l J

2 . 9 02 . 5 1 4r . 7 7 8| .5 r71 .4511 . 2 5 61 . 1 5 61 . 1 2 61.028

.968

.890

.850

.838

4 . 1 43 . 7 62 . 8 92.5061 . 7 7 6I . J I4T

1 . 4 5 2r .257l - 1.)4

1 . 1 2 61.027

.969

. 8 5 1

.838

< 1

10587II3#s#a 4

cJl

< 13#1 4

# Difiuse lines.A. Kobeite, Japan, heated in vacuo.B. Paringa River material, heated in vacuo.C. Paringa River material, heated in air.D. Kobeite, Japan, heated in air.

against this suggestion. Certainly there was no indication of any linesdue to rutile, brookite, or pseudobrookite.

The r-ray films obtained with the Paringa River mineral after beingheated to 1200o C. have been compared with those obtained from a largenumber of muitiple oxides of tantalum, niobium, titanium, and rareearths, but this provided no clue as to the true identity of the mineral inquestion, although it may be pointed out that a number of mineralsbelonging to this general group do give *-ray powder patterns of theuraninite-type after being heated to 620" C. in vacuo or in air for f-1hour. Among these are yttrotantalite, eschynite, brannerite, and some

1

< 110

A

8a

II3#s#) 4,, Jl

n4

a4- r

348 C. OSBORNE HUTTON

euxenites, including a specimen of Simpson's (1951, pp. 257-259) tant-euxenite from Cooglegong, Pilbara GoldfieJd, Western Australia.2

However, kobeite from the type locality-Shiraishi, Kobe-mura,Kyoto Prefecture, Japan-gives tc-ray patterns without being heated,

T,lsr,e 3. IrorxrNc ol Pownon Perrnnns ol Penrmce Rrvnn MrNonar.

Heated in air Heated in vacuo

(111)(200)(220)(311)(222)(400)(331)(420)(422)(s1 1)(440)(s31)(600)

d . L

2 9 02 . 5 1 4r . 7 7 81 . 5 1 71 . 4 5 1r . 2 5 6t . t J o

1 . 1 2 61 . 0 2 8

.968

.890

.850

.838

5 .O275.0305 0275 .0305 0255 .0255.0365 .0365 .0345.0295 .0325 .0285 .027

d . A

2 . 8 92.5081 . 7 7 21 . 5 1 31 . 4 71 . 2 5 4I . I J J

l . L z +

1 . 0 2 6.967.888.850.839

5.O125 .0155 . 0 1 15 .0185 .0105 .0145.0275.O245.0265 .0255 .O275 .0325 .034

Exceedingly faint lines, one in A and two in B, that are not permitted by the space-group are omitted.

A. Average ao:5.029 A.B. Average ao:5.027 A.

and after being heated in air or in vacuo, that are almost identical withthose yielded by the Paringa River mineral under corresponding cir-cumstances. This is doubly interesting since Takubo, Ukai, and Minato(1950, p. 511) have reported that after kobeite is heated to 900o C. for30 minutes hardly any signs of recrystallization were evident when themineral was subsequently examined optically and by r-ray difiractionmethods. Unheated kobeite gives a weak pattern (Table 1, column B)that is identical with that yielded by the Paringa River mineral exceptfor the presence of a few additional exceedingly faint, diffuse lines at

2 Arnott (1950, pp. 389, 399) obtained a similar pattern for tanteuxenite from Eleys,Western Australia, but he does not record the temperature at which the specimen washeated, nor the length of time of heating. The present writer has determined that if tant-euxenite is heated in vacuo at 1200" C. for t hour a tlpical euxenite-type pattern (Arnott,

1950, pp. 396-397; Berman, 1955, pp. 817-818) is obtained by r-ray diffraction.

KOBEITE FROM NEW ZEALAND

Tasr,n 4. X-Rev Dmln.ccrrox PowoBn Perrnnxs lon PenrNcn RrvnnMerr,nrer. AND KoBErrE, JAPAN

All specimens heated for t hour at 1200' C. Radiation CuKa:1.5418 A

d. meas. A d. meas. A d. meas A

5 . 4 64 1 33 . 7 13 6 1

3 0 72 . 9 1

2.78r

2.500

2.2812.O84

1 8061 . 7 6 8r . 7 3 41 . 7 1 5

I . 5 Z J

| . 2 5 41 . 1 7 5

I . t 4 l1 . t 1 71 . 1 0 41.0461 .033

.981

.969

.905

.865

.852

.839

d. meas. A

5 . 5 5+ . 1 5

3 . 5 93 . 2 93 .062 . 9 2

2 . 7 8 12 . 5 6 42 . 5 0 12.417

2.2862.O891 .8841.8091 . 7 7 0r . 7 + 2r . 7 2 11 . 6 3 01.6041 .5381 . 5 1 8

1 . 4 7 91 . 4 6 6| . 4 2 21 .3301 . 2 5 51 . t 7 4

l . t 4 l1 . 1 1 81 . 1 0 9t .0461 . 0 3 1

.982

.970

.906

.865

.852

.840

5 . 5 54 . l J

3 . 7 4

3 . 0 62 . 9 22.84412 . 7 8 9

2.500

2.286

1 . 8 1 1| . 7 7 0r . 7 3 71 . 7 2 2

1 . 5 4 21 . 5 1 81 .4955| . 4 7 2

L . 4 2 6

1 . 2 5 6r . r 7 51 . 1 5 9t . t42t . r r 91 . 1 0 51 .0481.032

.981

.969

.906

.864

.852

.840

5 . 4 64 . r 3J . / l

3 . 6 r

3 .072 . 9 1

2 .78 r

2.+952.4132 .3552 .274

1 .8801 .806r . 7 6 7| 7391 .7201 .6301 .6061 .5381 .518

r .4761.467

1 .254r . 1 7 4

1 .1401 . r171 .1061.045t .o32.980.969.905.865.851.839

< 1< 1< 1

1

110

4<r#<r#)

< 17

< 1J

I

< 1< 1

J

t4r#

2

,)1 J !L r

r#1 tL r1 !r t

r#1 !L T

1#1 4

< 1 #o !L t

< 1< 1< 1< 1

< 110

3

4

< 1

o< 1

4< l

4

a 4

< 12Llf

2#1 . !L T

1#1Jr1 !L r1 !

1 !r t

<r#1#

<r#) 4

< 11033

4

o< 1

4< 1

3+

< 11 A

< 1

22#

< 11 41 TL T

r#1 A

r#r#r#

<1#1 !L T

< 1 #l J l

11

111

10

< 1+

< l

2< 1< 1

7< 1

3I

< 1< 1

2J

1 !

1 4

<r#< 1

2a

I1I

I1#1111 4

<r#<r#

< l< 1< 1

1 Not present in most films of Paringa River Material.# Difiuse line.A. Kobeite, Japan, heated in vacuo.B. Paringa River mineral heated in vacuo.C. Parinsa River mineral heated in air.D. Kobeite, Japan, heated in air.Additional liries^arepresent in all films but it is not possible to measure them accurately

owinE to faintness and diffuseness.

J,C C. OSBORNE HUTTON

higher 2 d values in the film of Japanese kobeite. At the same time an-other film of Japanese kobeite exhibits a few elongated spots that in-dicate a very slight degree of orderl this is almost certainly due to rem-nants of the original structure.

Specimens of Japanese kobeite after being heated to 620" C. for 1hour in air or in vacuo, on most occasions yield powder patterns that areidentical to one another, and to the patterns found for the Paringa Rivermineral after being heated in air; a few spots were observed in one film.The heating of kobeite in air did not produce an increase in d-spacingsover those found for this mineral after being heated in vacuo;in this itdiffers from the Paringa River mineral. Comparisons of the d-spacingsof kobeite and of the Paringa River mineral, both heated to 620" C.are set out in Table 2.

X-ray diffraction powder patterns secured with both kobeite and theParinga River mineral heated to 1200" C. in air or in vacuo are distinctfrom those yielded at the lower temperature and a glance at Table 4makes it clear that there are no significant differences in these patternsof the high temperature modification. Although otherwise similar to thepatterns found to be constant (Table 4) one fragment of the paringaRiver material, after being heated in vacuo for t hour at 1200" C., yieldedan additional weak reflection at 2.844 A and the relative intensity of theIine at I.770 A is of the order of 2; in one other instance it is about 5,although the 2.844 A reflection is missing in this case. Furthermore, rwofragments of Japanese kobeite after being heated in vacuo gave X-rayfi lms with intensities of 2for the reflection at or close to l.?70 A. fnisline appears to correspond with and result from the persistence of therelatively strong (220) reflection found in all films of these minerals thathave been heated to the lower temperature of 620" C., but it is not clearwhy it should persist more distinctly in some instances and be almostabsent in most, unless this situation is connected with the apparentiocalization of radioactive material in the mineral, a condition that isclearly observed in the radiographs of the Paringa River mineral at least.In this connection it is of interest to compare the patterns obtained forthese two minerals that had undergone heating at 900o C. for 30 minutes,the conditions under which Takubo et al. (1950, p. 511) found no signifi-cant recrystallization had resulted in kobeite. In these films (Table 5)the uraninite-type pattern is dominant but with the strongest lines ofthe unique higher temperature phase or phases also present, so that thereflection close to L7i0 A is much more intense than those immediatelyon either side of it. It is interestins to observe that the reflection atapproximately 4.15 A is the only li,re that persists in films yielded by

KOBEITE FROM NEW ZEALAND 351

Tasln 5. Coupanrson ol X-Rev Dmlnecrror P.errnnNs Yrrr,neo nv Konrttr,J.lrew, arrnn FnLcuoNrs H,to BonN Sun;:ecmo ro Tbupnnerunrs or' 620o C.

(A),900'C., (B), AND 1200" C. (C) tN Vacuo

Radiation CuKa: 1.5418 A. Intensities determined visually

d. meas. A d. meas. A

4 . 1 . )

3 . 7 6

2 . 8 9

2 .505

r . 7 7 7

1 5 1 6

1 . 2 5 5

1 . 1 5 4r . 1 2 5

. 8 5 1

.838

5 9 4

+ .454 . 1 5J . / O

3 . 5 63 3 43 . 2 5

2 . 9 22 . 8 2

2 . 5 1 5

2.2842 . 0 7 31.9 t2

1 .808t . 7 8 2r . 7 Mr .720| . 6 2 7

1 . 5 3 8t . 5 2 0

1 .368

1 .255| 176t . l 4 l1 .129

r .0461.o32

.979

.970

.864

.852

.839

5 . 5 5

4 . I J

3 . 5 93 . 2 9

3 .062 . 9 22 . 7 8 12 . 5 6 42.50r2.4r72.2862.089

1 . 8 8 41 . 8 0 9r . 7 7 01 . 7 4 2t . 7 2 11 6301 . 6 0 41 . 5 3 81 . 5 1 8r . 4 7 9t .466

t . 4 2 2

1 .3301 .2551 . 1 7 4t . t4 r1 . 1 1 81 . 1 0 91.0461 . 0 3 1

.982

.970

.s06

.865

.852

.840

1

I

11

110

J

< 14

< 12

< 1

< l7

< 13I

< 1< 1

2Jna1 4L T

< 1 #

< 12a

1.028

.969

1 4

1II1 T

< 1 #<r#

< 1

I< 1< 1< l

I< 1

10I

7

< 1< 1

I

35L

< 1< l

< 16

< 1

21

< lI

< 1AJL

1#r#

2#) 4

3#

I< 1

10

4

8

7

1

1

2#, ,a

r#1#

<r#1J l

# Diffuse lines.

C. OSBORNE HUTTON

unheated material and material heated at 620" C., 900o C., 1000o C.,and 1200" c.; and furthermore it remains very weak throughout. Afterbeing heated to this intermediate temperature of 900o c. particle size isstill quite minute as evidenced by broadness or diffuseness of most lines.

The temperature of 1200' c. was chosen because work in progress inconnection with a wide variety of multipJe oxides of tantalum, niobium,and titanium has shown that this temperature is a convenient one inmost instances if reproducible r-ray diffraction patterns are to be ob-tained' However, subsequent experiments with kobeite and the paringaRiver mineral have shown that heating to 1000o c. for 40 minutes willgive identical and reproducible resuits.

NolrBNcrarunn

The x-ray diffraction study of the paringa River materiar before andafter heat-treatment clearly suggests that this mineral is identical, or atleast very closely related to, kobeite from Japan described by Takuboet al. (1950), but apparently distinct from a number of other multipleoxides of tantalum, niobium, and titanium. The actual appearance of thetwo minerals in their host rocks is strikingly similar, although the paringaRiver mineral exhibits no pronounced alteration to an anatase-rich prod-uct; this may be due to a difference in age. Finally the chemical data,although less complete than the physical, do not detract from this similarity. Therefore it is believed that the paringa River mineral is kobeite,and it is hoped that it will be foirnd in situ and more and better materialobtained that wil l allow a more thorough study than that reported here.

Study of the Japanese report at first leads one to the conclusion thatkobeite might be a high-titanium member of the euxenite-polycrase oreschynite-priorite groups, but eight specimens that undoubtedly belongto one or other of these groups yielded r-ray patterns after being heated to1200' c. that exhibited l itt le if any resembrance to patterns obtainedwith kobeite similarly treated; the same observation may arso be madefor fergusonite, including risdrite, brannerite, samarskite, and yttro-tantalite. These data rather definitely support the suggestion that kio-beite is a distinct and valid minerar species. and it is hoped that theresults of work in progress in connection with u .ru-b"i of murtipleoxides of tantalum, niobium, and titanium, mav provide further data onthis question.

Sounca

Granitic intrusions and pegmatites are known to outcrop at manylocalities in the general area from which the kobeite-bearing rock wasobtained, but so far as the writer is aware no tantalum-niobium bearinq

KOBEITE FROM NEW ZEALAND 353

minerals have been found in these rocks. However, it might be pointed

out that tantalian cassiterite is not a rarity in concentrates from sands

and gravels in many localit ies in Westland (Hutton, 1950). Again radio-

active minerals such as uranoan thorite, huttonite, monazite, xenotime,

and others (Hutton, 1950) have been found in South Westland sands

and gravels, although the actual source for these minerals has not been

determined as yet. The problem of the source of kobeite is complicatedfurther by the existence of large quantities of glacial debris, much of

which has been resorted bv rivers and streams.

Acr<NowrBocMENTS

I wish to acknowledge the opportunities provided for this research by

the award of a John Simon Guggenheim Foundation Feilowship. To Dr.

T. Ilinato of Kyoto University, Japan, I am most grateful for his kind-

ness in sending me specimens of kobeite from the type locality, and I am

much indebted to my friend Mr. Yoshihiko Shimazaki for his fuil and

careful translation of the paper on kobeite by Takubo, Ukai, and Minato.A grant from the University Committee on Supplementary ResearchGrants permitted the purchase of special high-sil ica tube and otheritems; this assistance was much appreciated.

Rrlnnnrces

Anwott, R. J. (1950), X-ray diffraction data on some radioactive oxide minerals: ,4m.

M'ineral . 35. 386-400.Bonnex, J. (1955), Identification of metamict minerals by rtay difiraction: Am. Mineral..,

40, 805-827.HurroN, C. O. (1950), Studies of heavy detrital minerals: Geol. Soc. Am.8u1,tr.,61' 635-

/ t o .--- (1951), Allanite from Yosemite National Park, Tuolumne Co., California: Am.

Minerol., 36, 233-248.Mennr.r, J. P. (1948), Some applications of autoradiography: Intern. Geol. Congress, Repl.

18tk Session, Gt. Britain, Pt. II, pp. 80-85.SrursoN, E. S. (1951), Minerals of Western Australia, 2nd. vol., esp. pp. 257-261, Govt"

Printer, Perth, Western Australia.Sw,rNsow, H. E., exr Terce, E. (1953), Standard *-ray diffraction patterns: Nat. Bur.

Stand,ard.s Circ., 539, YoL.I.Terueo, J., Ur<er, Y., ,lNo MrN.tto, T. (1950), Studies on the minerals containing rare

elements (Part 11); Kobeite from Shiraishi, Kobe-mura, Nakagun, Kyoto Prefecture:

fourn. Geol. Japan,56,663, 509-513 (in Japanese).

Manuscript reeeiled. Au,g. 31, 1956.