American Mineralogist, Volume 62, pages J95-397, lg77
NEW MINERAL NAMES*
MrcHenl Flprscunn ANDJoHN JeMsoR
Schreyerite*
O MeoENeecs nNo K. Scsprtrznx (1976) Schreyerite (VrTisOr),
ein neues Vanadium Mineral aus Kenya. Naturwissenschaften,
63.293-294.
The mineral occurs in highly twinned unmixed grains up to 30
m i c r o n s i n s i z e i n v a n a d i u m - b e a r i n gr u t i l e t h a t o c c u r s a s i d i o m o r _
p h i c c r y s t a l s i n k o r n e r u p i n e - b e a r i n gq u a r t z - b i o t i t e - s i l l i m a n i t e
g n e i s si n t h e K w a l e d i s t r i c t , K e n y a . A s s o c i a t e dm i n e r a l s i n c l u d e
kyanite, muscovite, apatite, tourmaline, graphite, pyrrhotite, chalcopyrite,and pentalandite.
Microprobe analysis (not given) gave the formula
(VorrCroouAlo.o,)rTirOr,with traces of Mg and Fe. Single-crystal
s t u d y c o u l d n o t b e m a d e b e c a u s eo f t h e t w i n n i n g . D e b y e a n d
Gandolfi films were indexed on a monoclinic cell with a 7.06, b
5 . 0 1 , c f 8 . 7 4 A . , p 1 1 9 . 4 . . T h e s t r o n g e s tl i n e s ( p r i v a t e c o m m u n r c a tion from O. Medenbach, given erroneously in the paper) are4.075
The mineral occurs as poorly developed crystals up to 60-70 cm
i n s i z e ,u s u a l l y t w i n n e d o n { l l 0 } a n d { 3 1 0 } , s i m u l a t i n g h e x a g o n a l
symmetry Color blue to violet blue, luster vitreous. H 7-7!; cleavage {100} imperfect, parting {001};sp gr 2.77. Optica[y biaxial,
n e g a t i v e , a1 . 5 6 1P, 1 . 5 7 2 , t 1 . 5 7 6 , 2 1 / 6 6 " , r( u w e a k ; p l e o c h r o i c
with Xcolorless, Iblue, Z paleblue, Y > Z> X,orientation X =
c,Y:b.
The mineral occurs near Dolni Bory, western Moravia, in the
a l b i t e z o n e o f p e g m a t i t e si n g r a n u l i t e sa n d g e n i s s e s .
The name is for Professor Josef Sekanina, who first found the
m i n e r a l i n 1 9 2 8 .M . F .
Strf,tlingite*
G. HsNrscHsL AND H.-J. Kuzw (1976) Stratlingite, 2 CaO
Alros
SiO,
8HrO, a new mineral NeuesJahrb. Mineral..
Monatsh. 326-330 (in German),
(m) (00a),3.381(m) (204),2.874(sx2t3),2337(vs)
(ots),2.432
( w ) ( 2 l l ) . I n p a r t r h e l a m e l l a a r e o r i e n t e da f t e r ( l 0 l ) o f r u t i l e . T h e
m i n e r a l i s b l a c k . H I 1 0 0 - 1 2 0 0k g l s q m m . R e f l e c t a n c ea t 5 g 9 n m =
2 l p e r c e n t , l e a d i n g t o n 2 . 7 . l n s e c t i o ns h o w s p l e o c h r o i s m f r o m
white to brownish. Insolublein acids.
The name is for Professor Werner Schreyer of Ruhr University.
B o c h u m ,G e r m a n y .M . F .
Sekaninaite*
J . S T A N E KA N D J . M l s K o v s r v , ( 1 9 7 5 ) S e k a n i n a i t e ,a n e w m i n e r a l
of the cordierite series, from Dolni Bory, Czechoslovakia Scr
Fac Sci Nat Ujep Brun , geol /, no. 5,21-30.
Chemical analyses of blue and violet-blue samples agreed
c l o s e l y ;t h e f o r m e r g a v e S i O , 4 5 . 1 0 ,T i O , 0 . 0 4 , A l , O , 3 0 . 6 3 , F e r O ,
0 . 9 1 , F e O 1 7 . 8 5 ,M g O 1 . 6 9 ,M n O 0 . 9 2 , C a O 0 . 3 9 , N a , O 0 . 6 8 ,K , O
0.03, H,O+ I 84, HrO 0 12, sum 10020 percent,giving (Nao ,nCaoo,)
( F e f , l r M g o , r M n o o . ) ( A l , , o F e f . l , S i o , 3 ) A l , S i n O , ,0 6 7 H r O , t h e F e a n a l o g o f c o r d i e r i t e .T r a c e s o f Z n , C r , B e , G a , A g , C u , a n d N i
were found spectroscopically. The infrared absorption spectrum
i s g i v e n . D T A a n d T G A c u r v e sa r e g i v e n .T h e w a t e r i s l o s t c o n tinuously up to 500' A small exothermic reaction (oxidation of
F e ? ) w a s o b s e r v e da t 7 8 0 '
X - r a y p o w d e r d a t a w e r e i n d e x e do n a c e l l w i t h a l 7 . l g 6 . b 9 . 5 2 7 .
c 9.2984, spacegroup probably Cccm. The strongestlines (3g
g i v e n ) a r e 8 s 8 3 ( 1 0 0 )( 2 0 0 ,I l 0 ) , 4 . 0 8I ( 8 3 ) ( I t 2 ) , 3 . 3 8 6( 1 0 0 )( 3 l 2 ) ,
3 376 ( 100) (022), 3 t43 (64) (222), 3.076 (74) (5 I l, 42 I 3.043 (57)
),
fi31).
* Minerals marked with an asterisk
after the name were approved before publication by the Commission on New Minerals
and Mineral Names of the International Mineralosical Association
H . - J . K u z e r , ( 1 9 7 6 ) C r y s t a l l o g r a p h i cd a t a a n d t h e r m a l d e c o m p o sition of synthetic gehlenite hydrate, 2 CaO . AlrO, . SiO,. 8HrO.
Neues Jahrb Mineral , Monatsh 319-325 (in English).
Qualitative microprobe analysisshowed Ca, Al, and Si as major
constituents! with less than I percent Fe, but a quantitative analysis could not be made because the mineral dehydrated in the
electron beam to a powdery residue unsuitable for probe analysis.
E a s i l y d e c o m p o s e db y d i l u t e H C l .
The mineral was synthesizedin single crystals by the slow hydrat i o n o f c a l c i u m a l u m i n u m s i l i c a t eg l a s s e si n s a t u r a t e ds o l u t i o n s o f
Ca(OH), at 20"C for 120 days. X-ray patterns of natural and
synthetic material were essentially identical. The strongest X-ray
l i n e s o f t h e n a t u r a l m a r e r i a l ( 1 8 g i v e n ) w e r e 1 2 . 5( 1 0 0 ) ( 0 0 3 ) , 6 . 2
( 7 0 ) ( 0 0 6 ) , 4 . 1 6( 1 0 0 ) ( 0 0 9 ) , 2 . 8 7 ( 7 0 )( l l 0 ) . T h e m i n e r a l i s t r i g o n a t ,
s p a c eg r o u p R 3 , o r R 3 , a 6 . 7 3 7 t 0 . 0 0 5 , c 3 7 . 5 9 + 0 . 0 5 A . , Z : 3 ,
s p g r c a l c d . I 9 5 , s p g r m e a s u r e d( s y n t h e t i c ) 1 . 9 . T h e s y n t h e t i i
c r y s t a l sh a d a 5 . 7 4 7 t 0 . 0 0 1 , c 3 7 . 6 4 + 0 . 0 1 4 .
The DTA curve shows endothermic breaks at l3l, l8t, and
226", and a sharp exothermic break at 990.C. The loss of weight
c u r v e s h o w s a l o s s o f 4 H r O t o I 3 8 o , w h e n a n a b r u p t d e c r e a s ei n a
and c occurs. The exothermic break corresponds to the crystallization of gehlenite.
The mineral is colorless to light green. Cleavage basal perfect.
U n i a x i a l , n e g a t i v e ,o | 5 3 4 ; s y n t h e t i c m a t e r i a l h a d < o1 . 5 1 9 .
The mineral occurs in a metamorphosed limestone inclusion
within the basaltic lava flow at Bellerberg, Mayen/Eifel, as plates
0 . 1 - 0 . 5 m m i n d i a m e t e r I t i s a s s o c i a t e dw i t h n e p h e l i n e ,m e l i l i r e ,
garnet, thomsonite, gismondine, ettringite, and hydrocalumite,
a n d a w h i t e u n i d e n t i f i e di n c r u s t a t i o n .
The name is for W. Stretling, who synthesized the mineral
( " S t r a t l i n g ' s c o m p o u n d " ) i n 1 9 3 8 .T y p e m a t e r i a l i s a t t h e U n i v e r sity of Erlangen, Niirnberg, Germany.
Note This is the second "gehlenite hydrate" mineral, compare
b i c c h u l i t e I A m M i n e r a l . , J 9 , 1 3 3 0( 1 9 7 4 ) . ] M . F .
395
NEI.YMINERAL NAMES
396
fhalcusiter
V . A . K o v l r - s N K E R ,I . P . L e p u t t x , q , T . L . E v s r t c N e B v e l N o V . M .
I z o r r r o ( 1 9 7 6 ) T h a l c u s i t e ,C u , , , T l , F e r * , S . , a n e w t h a l l i u m
sulfide from copper-nickel ores of the Talnakh deposits Zap
Vses Mineral Obshch., 105,202-206 (in Russian)'
Electron microprobe analyses were made, using as standards
Cu, Fe, FeS,, synthetic Cu,TlzFeS., and synthetic TlSbSz' These
g a v e T l 5 2 . 2 , 5 3 , 4 ;C u 2 2 . 6 , 2 0 . 5 ;F e 9 . 1 , 9 . 9 ; S 1 6 . 3 ,1 6 5 ; s u m
1 0 0 . 3 p e r c e n t , c o r r e s p o n d i n g t o C u r r r T l , o r F e rr r S . a n d
C u r u , T l r o r F e r r " S ns, o t h a t J i n t h e f o r m u l a a b o v e : 0 . 2 1 4 ' 4 9
Analyses considered less reliable, of 8 smaller grains, gave Tl
5 1 . 9 - 5 6 . 4 ,C u 1 6 . 6 - 2 0 I , F e 9 . 3 - 1 0 . 6 p e r c e n t .
T h e X - r a y p a t t e r n h a s s t r o n g e s tl i n e s ( 1 4 g i v e n ) : 3 ' 7 3 ( 8 ) ( 1 0 1 ) '
2 . e l( r 0 ) ( 1 0 3 ) , 2 . 5( l30 X l l 2 ) ,1 . 9 4(15 ) ( 2 0 0 )1, . 7 1(75 X 1 1 6 )
This was indexed by comparison with its Se analog, bukovite
c
fAm Mineral , 57, 1910(1972)1,as tetragonal, a 3.88240.005'
13 25+0.02A. The space group is Am2, A2m, I4mm, 1422, or
1 4 / m n S p g r c a l c . 6 . 5 4 ( Z = 1 ) , m e a s u r e df o r s y n t h e t i c m a t e r i a l
6.r5.
The mineral occurs in platy deposits, rarely elongated' mostly as
grains l0-15 microns in diameter Cleavage parallel to elongatton
B r i t t l e . M i c r o h a r d n e s s ,8 2 - 9 2 , a v 8 8 k g l s q m m a t l 0 g l o a d . I n
reflected light weakly birefringent with color change from pale gray
with brownish-lilac tint to dark gray. Reflectancesare given at l6
wave lengths(440 lo 740 nm); Rg'and Rpl are' resp: 460' 31.3'
3 0 . 4 ; 5 4 0 , 2 9 . 9 , 2 8 . 4 ; 5 8 0 , 3 0 . 3 , 2 7 . 9 ; 6 6 0 , 3 3 7 , 3 0 . 6 p e r c e n t .A n isotropic with colors from light yellowish to very dark gray.
The mineral occurs in pentlandite-cubanite-chalcopyrite ores,
T a l n a k h d e p o s i t , a s s o c i a t e dw i t h m i n e r a l s o f P t a n d P d a n d a l s o
with altaite, galena, sphalerite, and djerfisherite.
T h e n a m e i s f o r t h e c o n s t i t u e n t sT l , C u , S . T y p e m a t e r i a l i s a t t h e
M i n e r a l o g i c a l M u s e u m , A c a d e m y o f S c i e n c e ,U S S R , M o s c o w '
M.F.
It is stated that Yu. M. Shipovalov in 1965 reported a similar
mineral from Kazakhstan with a 14.90, b l0'60, c 7.08A., which
differed somewhat from the Kola mineral in composition,sp gr
and refractive indices (not given) Shipovalov used the name yftisite for this mineral.
Balko and Bakakin have studied the Kola mineral and find it to
be orthorhombic, space group Cmcm, with a 14.949, b 10'626, c
7.043A. Deriving a formula from the incomplete analysis above is
difficult. with some assumptions such as partial replacement of Ti
by Sn (private communication from Pletneva, et al.) the formula
proposed is (Y,Re).(F,OH)o(Ti,Sn)O(SiO1), or possibly
(Y,Re,Ca).(F,OH,HzO)e(Ti,Sn)O(SiO{),-'(OH)*1, and for the
Kazakhstan mineral (for which no analytical data are given):
(Y,TR).IF'(O,F).]Al(Ti,Fe,Al)O(SiO.).
The name is apparently for the composition.
Discussion This appears to be a new mineral, but it should not
have been named until better chemical data were available and the
data for the Kazakhstan mineral were available' M.F.
NEW DATA
CatoPtrite, Yeatmanite
P. B. Moons, Tnr,lulnu Annrt lro G. D. BnuNrox (1976)
Catoptrite, (Mn3+Sb!+) (Mn3+ALSL)O28, a novel close-packed
oxide sheet structure. Neues Jahrb. Mineral , Abh ' 127' 4'l-61.
Single crystals from LAngban, Sweden, shown by X-ray study to
be identical with type material, were studied. A microprobe analys i s b y A . J . I r v i n g g a v e S b , O u2 2 ' 4 , 5 i O , 8 . 0 , A l r O , 1 0 . 9 'M n O 5 4 ' 3 '
M g O 3 . 7 , F e O 2 . 5 , Z n O n o n e , C a O < 0 . 0 5 ,s u m 1 0 1 . 8p e r c e n t l t i s
: 2
m o n o c l i n i c , C 2 / m , a 5 . 6 1 7 , b 2 3 . O 2 ,c 7 ' 0 7 9 A ' P 1 0 1 " 2 3 ' , Z
formula units of the formula above.
It is suggestedthat yeatmanite is closely related to catoptrite and
that its formula can be given as (M n3+Sbl+XMn?+Zn"SL)O'. M.F.
Derbylite
Yftisite
AND TAKAHARU ARAKI, (1976) Derbylite'
B. Moorr
Fe:+T r+Sbe+Or(OH), a novel close-packed oxide structure'
Neures Jahrb Mineral , Abh , 126,292-303.
N . I . P r - B r n e v l , A . P . D r N I s o r a n d N . A . E I - l N r .( 1 9 7 1 ) A n e w
variety in the group of rare-earth fluosilicates. Mater Mineral
Kol'sk Poluost 8, 1'16-179(in Russian).
P.
V . P . B A L K o l N r V . V . B n r , c r l N ( 1 9 7 5 )T h e c r y s t a ls t r u c t u r eo f t h e
n a t u r a l y t t r i u m a n d r a r e - e a r t h f l u o r o t i t a n o s i l i c a t e ,( Y , T R l (F,oH)"TiOlSiOnl,, (yftisite).Zh Sftukt Khim ' 16,837-842-
A structural study of material from the type locality showed it to
be monoclinic, space group P2t/ m, a 7 .160, b 14.347, c 4.9'lOA, P
104.61", Z = 2 formula units of the formula above (not Fe2+ and
S b u +a s p r e v i o u s l y g i v e n ) . M . F .
The first paper describes an unnamed mineral from the Kola
Peninsula, USSR, an accessorymineral in silicified alkali granites
near the contact with gabbro-anorthosite. Partial analysis gave
y , o 3 3 6 . 8 2 ,T R ' O . l 3 8 9 , T h O , 1 . 4 3 'T i O , 9 . 6 9 S i O , 1 3 . 2 4 ,F 8 9 3 '
H r O + 7 . 0 7 T h e r a r e e a r t h sw e r e L a 0 . 9 , C e 8 5 , P r n o n e ' N d 7 . 6 '
S m 5 . 1 ,E u 0 . 4 , G d 5 . 5 ,T b 0 . 8 , D y 2 4 . 6 ,H o 3 . 4 , E r 2 0 . 8 'T m 2 l '
Yb l8 2, Lu 2 1 percent, i e , heavy lanthanides dominate.
The mineral occurs as prismatic crystals up to 6-7 mm long,
transparent yellowish, luster vitreous to greasy, H 3.5-4' Sp gr
3.96, no.cleavage.Optically biaxial, negative,2Y large, r ) u
distinct, af.690,01.705, ll.7l0-1.7 12,has anomalous blue inter-
Eglestonite
K
MeR.etrrn AND J. ZEMANN (1976) Restudy of the mercury
mineral eglestonite:crystal structure, chemical composition, and
synthesis. Tschermaks Mineral. Pelrogr' Mitt.,23, 105-115 (in
German).
Study of the crystal structure of eglestonite showed it to be
cubic, space group la3d, a : 16.036A. This gave for the cell
content Hg"eCl."Osz,not compatible with the presence of Hgr
groups, indicating a pure Hgr+ compound. The mineral was
color
ference
+
0
'
0
1
'
synthesizedby heating calomel with KOH solution at 160o.AnalyX - r a y d a t a w e r e i n d e x e d o n a n o r t h o r h o m b i c c e l l ,a 1 5 . 0 4
sis of the product for HzO by Penfield method gave HrO 0.62'0.7 5'
b 1 0 . 6 3 + 0 . 0 1 ,c 7 . 0 5 2 + . 0 0 3 4 . T h e s t r o n g e s tl i n e s ( 6 2 g i v e n ) a r e
percent (theory for HgeClrOzH : 0.67Vo). The formula
0.74
2.667(
10X040)'
3.09e(
l0x 13I ),
3.s26(7X002),
3.727(7)(22r),
(Z : 16) is confirmed by the presenceof a short O-O
)'
1 . 7 6 6 ( 1 0 ) ( 6 4 1 , 0 t0. 4' 7t)4, ( t 0 ) ( s s 2 8 , 3 5 2HguCl,OrH
l,s2l(9)(640),
I (7X10'6'2). distance, characteristic of
1.09
2), r.442(8X643
r.5se(8x005855
), l .104(7X426),
a hydrogen bond. M.F.
NEW MINERAL
Goongarrite
N. N. Mozcovn, Yu. S. Bonoonev, L. E. SyRrrso nNo D. p.
Ror,rlNov (1976) New data on goongarrite (warthaite) and
about the identity of heyrovskyite with goongarrite. Neues
Jahrb Mineral. Abh , 127,62-83.
397
NAMES
s t a t i n g r e d e f i n e dg o o n g a r r i t e . I n s t e a d , t h e d a t a p r e s e n t e di n t h i s
p a p e r s h o u l d b e c o n s i d e r e da s s u b s t a n t i a t i n gh e y r o v s k y i t e ,p a r t i c ularly the formula Pb,oAgBiuSr"as extending its compositional
r a n g e .J . J .
Weibullite, Wittite
The authors give microprobe analyses,X-ray data (both powder
and single crystal), reflectivities, microhardness determinations,
e/c, which are in good agreementwith the propertiesof heyrovskyi t e , a s i s r e c o g n i z e db y t h e a u t h o r s . T h e n e w r e s u l t sw e r e o b t a i n e d
f r o m m a t e r i a l f r o m 2 l o c a l i t i e s :( l ) " p l a t y l i l l i a n i t e " f r o m S p o k o i n oye, Transbaikal; originally described by Syrit'so and Senderova in
l96a; Q) "warthaite" from Vask6, Hungary. These specrmens
consist predominantly of galena-cosalite intergrowths, with minor
areas of heyrovskyite The galena-cosalite-heyrovskyite interg r o w t h s a p p e a r t o b e p s e u d o m o r p h sa f t e r h e y r o v s k y i t e .C r y s t a l s
consisting of intimate intergrowths of cosalite and galena, but with
the heyrovskyite morphology, give bulk compositions appropriate
for heyrovskyite; it is likely, therefore, that the intergrowths represent unmixing from what was originally heyrovskyite Similar int e r g r o w t h sa r e p r e s e n ti n m a t e r i a l d e s c r i b e do r i g i n a l l y a s " g o o n garrite" (Simpson, 1924) and "warthaite" (Krenner and Loczka,
1 9 2 6 ) ,t h e b u l k c o m p o s i t i o n so f w h i c h a l s o c o r r e s p o n dw e l l w i t h
h e y r o v s k y i t e .B o t h g o o n g a r r i t e a n d w a r t h a i t e h a v e l o n g b e e n r e c o g n i z e dt o b e m i x t u r e sa n d w e r e d i s c r e d i t e do n t h e b a s i so f m i c r o s c o p i c a n d p o w d e r X - r a y d i f f r a c t i o n s t u d i e s( T h o m p s o n , 1 9 4 9 ) .
Mozgova et al argue that the name goongarrite should be used
for the mineral now called heyrovskyite. They seem to agree that
the original descriptions and analyseswere undoubtedly based on
mixtures However, they point out that the name goongarrite has
been used for the well-known synthetic homogeneous phase
Pb4BirS?which corresponds to Simpson's theoretical goongarrite
formula. They also pointed out that Godovikov el c I (1967) recognized that the synthetic phase was similar to the natural ,,platy
l i l l i a n i t e " o f S y r i t s o a n d S e n d e r o v a( 1 9 6 4 ) ,a n d c o n c l u d e dt h a t t h e
"platy lillianite" was a natural occurrence of goongarrite
Discussion Heyrovskyite was named in l97l (Kloninsky et at )
after receiving IMA approval. The literature is replete with references to obscure, discarded, or newly-coined mineral names without supporting data. Goongarrite is no exception. The identity of
the synthetic phase (hypothetical goongarrite : synthetic heyr o v s k y i t e ) w i t h " p l a t y l i l l i a n i t e " w a s e s t a b l i s h e db y G o d o v i k o v e l
a/ solely on the basis of their similar powder X-ray patterns and a
very crude similarity in composition. Mozgova et al. have reexamined the "platy lillianite" of Syritso and Senderova and conclude
t h a t t h e o r i g i n a l a n a l y s i sw a s m a d e o n a m i x t u r e o f g a l e n a a n d
cosalite in exsolution intergrowths and of "platy lillianite" = heyrovskyite (which they prefer to call goongarrite). Cell dimensions
o f t h e " p l a t y l i l l i a n i t e " a r e o : l 3 . 7 l t } . O z , b : 3 t . 2 4 + O . 0 5 ,c 4.10+0.024, in excellent agreementwith those of natural and
s y n t h e t i c h e y r o v s k y i t e .C e l l d i m e n s i o n so f " p l a t y l i l l i a n i t e " w e r e
s t a t e db y S y r i t s oa n d S e n d e r o v at o b e b : 1 2 . 8 + 0 . 1a, : 3 1 . 0 + 0 . 1 .
c = 4 . 1 5 X 0 . 0 2 ,p r e s u m a b l ye r r o n e o u s .
In conclusion, the mineral which was named heyrovskyite entailed the first complete description of a natural occurrence of this
compound. Presumably the authors could have chosen to apply to
it the ill-defined and discredited name goongarrite There now
s e e m st o b e n o j u s t i f i c a t i o n i n d i s c r e d i t i n gh e y r o v s k y i t ea n d r e i n -
Zornsr JoslN eNo Peul Prcor (1976)Definition nouvellede la
weibullite et de la wittite. C R Acad. Sci. Paris, Ser. D.,282,
137-139 .
Restudy was made of material from the type locality, Falun,
S w e d e n ,o n s p e c i m e n si n t h e E c o l e d e s M i n e s , P a r i s .
Weibullite is orthorhombic, space group Pc2rn or Pcmn, a 15.39
+ 0 0 2 , b 4 . 0 6 8 + 0 . 0 0 4 ,c 5 3 . 8 + 0 5 4 , Z : 4 . T h e s r r o n g e s t X - r a y
l i n e s ( 4 5 g i v e n ) a r e 3 8 4 7 ( 1 0 ) ( 4 0 0 , 0 . 0 . 1 4 )3, 2 6 8 ( 8 ) ( 2 1 7 ) , 3 0 8 0
( 9 ) ( 2 1 9 , 30 l 4 ) , 3 . 0 f9 ( 7 X 4 0 I l , 3 0 1 4 ) ,2 . 8 1 1( 7 ) ( 3 t 9 , 2 . t . t 2 ) .
M i c r o p r o b e a n a l y s e sg a v e P b 2 9 . 7, 2 8 . 2 : B i 4 6 6 , 4 6 . 8 ; A s 0 . 8 , - ;
S e 1 5 . 3 ,l 5 3 ; S 9 . 6 , 9 8 ; s u m 1 0 2 . 0 1
, 0 0 . 1p e r c e n tc; o r r e s p o n d i n g t o
P b u B i . S e r S 'o r p e r h a p s P b u B i . S e r S , o .
P r o b e a n a l y s e so f w i t t i t e g a v e P b 3 3 . 2 , 3 3 . 2 ; B i 4 5 . 7 , 4 5 . 3 ; S e
1 0 . 0 ,9 . 4 ; S I 1 . 4 , 1 2 . 0 ;s u m 1 0 0 . 4 ,9 9 9 p e r c e n t ,c o r r e s p o n d i n gt o
Pb"Bi,rSerSro.
T h e X - r a y p a t t e r n o f w i t t i t e c o r r e s p o n d st o t h a t p u b l i s h e d b y
Peacock and Berry (Uniu Toronto Studies, Geol Ser 44,48-69,
1 9 5 0 ) , w h o g a v e a 1 8 . 0 3 4 + 0 0 1 , b 4 . 0 4 0 + 0 . 0 0 2 , c 1 7 . 5 3 0+
0 0034. (Ed. note: see also Am Mineral., 6 t , 839-852, 1976).
Unnamed (Ce,La,Nd)NbOo :Brocenite
I Beta-fergusonite-( Ce ) J
A I. CHesxe AND E. YA. MnncHeNxo (1976)A new rare-earth
n i o b a t e f r o m c a r b o n a t i t i e s .G e o l G e o f z , n o . 4 , p . l 4 l - 1 4 3 ( i n
Russian).
A n a l y s i s o f t h e m i n e r a l g a v e N b r O u 4 1 . 7 8 ,T a r O u I 0 0 , T i O , 0 . 0 5 ,
Fe,O, 0.66, RErOs 5l 12, CaO 1.20, loss on ignition 2.55,
(MgO+ZrO,*ThO,+UaO6) 1.89, total 10025 percent. Spectrographic analysis by V G. Teplyakova of the rare earths gave La
2 3 0 , C e 2 9 . 0 , P r I 0 , N d 3 5 . 0 ,S m 0 7 , E u 0 . 1 , c d 0 . 2 , E r 0 . 3 , T m
0 . 6 2 , Y b 0 . 1 , Y 0 . 4 p e r c e n t ,T b , D y , L u n o t f o u n d T h e f o r m u l a i s
(REo
o u U oo r T h oo r X N b or 6 T a oo , F e oo s ) O n .T h e m i n e r a l i s i n "uCao
s o l u b l ei n a c i d s .D T A s t u d y s h o w e de x o t h e r m i cb r e a k sa t 3 6 5 . a n d
675', the latter marking transition from metamict to crystalline.
The infrared spectrum shows bands (1620 and 3450cm r) characteristicof molecular HrO.
The mineral is metamict,X-ray amorphous After beingheated
at 700o, it gave an X-ray pattern identicalwith those of synthetic
CeNbOn,NdNbO{, PrNbOn(ASTM nos. l4-501, t4-596,14-597).
T h e s t r o n g e s lt i n e s ( 3 1 g i v e n ) a r e 3 . 2 1 ( l O X l l 3 ) , 3 . 0 4 ( t 0 X 2 t 2 ) ,
2 . 8 4 ( 6 ) ( 2 2 0 ) , 1 . 9 7 7 ( s ) ( 4 0 0 ) ,t . 9 0 4 ( 6 ) ( 3 2 3 , 3 t 4 ) , t . 6 7 e ( 9 x 3 3 0 ) ,
1 . 6 0 5 ( 9 X 4 1 4 , 1 l 7 1) ,. 2 5 8 ( 6 X 4 1 7 T
) .h i s i s i n d e x e do n a m o n o c l i n i c
c e l l , a 5 1 7 0 , b l l 3 7 2 , c 5 4 9 7A , p 8 5 " 2 0 ' .
The mineral is red to dark red, streak pale rose. Sp gr 5.44.
B r i t t l e , f r a c t u r e c o n c h o i d a l .I s o t r o p i c , n 2 . 1 5 5 .I t o c c u r s i n a c a r b o n a t i t e , l o c a l i t y n o t s t a t e d . I t i s n o t n a m e d , b u t i s s t a t e dt o b e a
m i n e r a l n o t p r e v i o u s l yf o u n d .
Di.scu.ssion.
This is clearly identical with brocenite [better referred to as beta-fergusonite-(Ce)l; see Am Mineral, 60, 4g5
0975). M.F.