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166 BOOK REVI EWS
and limi tations are explained. Counter methods are
next discussed, and reference is made to the pro-
cedures for correcting intensity data for use in
subsequent structure determination. The essential
steps in solving a crystal structure are then set out,
and the methods of refinement described. The aim
throughout is to explain the procedure to be
adopted by the practical crystallographer who does
not want to be distracted by digressions into full
background theory or the more specialized aspects
of crystal structure de termination. The style is clear
and very readable, and one is conscious of being
given the experimental know how' that can only
come from an experienced crystallographer who
has herself met all the practical difficulties and
overcome them. The usefulness of the book as a
crystallographers' 'workshop manu al' is reinforced
by a final chapter summarizing and assessing the
advantages of the various techniques against the
effort likely to be expended in applying them and
the cost of the necessary equipment. An extension
of the very brief one-page section on direct methods
would have been an advantage in view of the
prominence of these techniques in current research,
but this is a minor criticism of what is on the whole
a very well-balanced account.
The book can be warmly recommended to
undergraduates or graduates who wish to learn
quickly the elements of the subject in order to apply
them in the course o f a project or research. It is well
produced, and the diagrams are clear. Compre-
hensive references are provided for those who wish
to read further; and at s the paperback edition
should be within the reach of most students even at
the current depressed level of grants.
S. G. FLEET
Kerr (P. F.),
Optical ineralogy
(fourth edition).
New York (McGraw Hill Book Company), I977.
xvi +492 PP., 427 figs. Price s
This is the latest edition of a textbook that has
always been popular with students because it sets
out in a well-arranged way the properties needed to
identify minerals in thin section. It is in two parts,
the first giving the principles of mineral optics and
the second describing each mineral systematically.
There are relatively few changes from the preceding
edition, but instructors who may be tempted to
prescribe the book for class use should be aware
that it has many serious deficiencies.
The most obvious shortcomings arise from the
failure to revise the new edition to take account of
developments in the subject. For example the
differences between high- and low-temperature
feldspars seem to be only grudgingly recognized,
and low-temperature plagioclases continue to be
described as 'normal plagioclase'. The deter-
minative curves for plagioclase based on 2V and
the angle of the rhombic section are taken from
publica tions of I931 and I9I 9 respectively and
completely ignore subsequent discoveries on the
effects of variation in structural state. Albite is
listed as optically positive with a 2V of 77 ~ to 82 ,
which is only true of the low-temperature variety.
Non-metric measurements continue to be used,
such as miles per second on p. 55 and pounds per
square inch on p. 43o, and for monoclinic minerals
fl is usually quoted as an acute angle. A really
bizarre entry is that ofiddingsite, which although in
reality a poorly characterized mixture is given a
most detailed description that includes crystal
system, refractive indices, 2V, cleavage directions,
and pleochroic scheme. There is no explanation of
the real nature o f such materials as opal or limonite,
even though they are much better understood than
when the first edition of the book appeared. Some
of the updating that has been done is of dubious
value. The electron micrographs and phase dia-
grams do not contribute much to a handbook on
optics, especially when liquidus temperatures are
referred to as 'temperatures of forma tion' (p. 286).
Errors abound. Wrong chemical formulae are
given for augite, biotite, chabazite, dumortierite,
glauconite, heulandite , illite, phlogopi te, staurolite,
stilbite, and t rona, Chabazite is wrongly described
as monoclin ic and erionite as orthorhombic, while
the refractive indices quoted for the latter are much
too high ( ~ r5 4 instead of ,,- 1.47 . There is a
general disregard of the principles of crystal chem-
istry. Formulae of minerals are sometimes quoted
as though they were made up of separate molecules,
e.g. kaolinite A1203.2SIO2.2H20, while others are
presented in a more modern form. The treatment of
hydroxyl ions is capricious, and they are shown as
(OH) in talc and chlorite, as H in prehnite, serpen-
tines, axinite, chloritoid, stilpnomelane and
lawsonite, and as HzO in kaolinite, chamosite, and
several others. In heulandi te and stilbite, molecular
water is written simply as H. Mclilite is grouped
with the tectosilicates, but glauconite is not classed
either as a mica or a clay mineral. It is suggested
that feldspathoids may be considered as 'silica-
deficient feldspars'. In places, isomorphous sub-
stituents are written without a comma, e.g.
(KNa)AISi30s for microcline on p. 285.
There is a great deal of carelessness in the
systematic descriptions, with students being led
into pitfalls that should be guarded against. The
interference colour of albite is described as 'pale
yellow of the first order, about the same as quartz in
the same section', with no reminder that this
would be the
m a x i m u m
interference colour of a
number of grains (and then only in a rather thick
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B O O K R E V I E W S
s e c ti o n ). T h i s i s i m m e d i a t e l y f o l l o w e d b y t h e s t a t e -
m e n t t h a t t h e m a x i m u m e x t i n c t io n a n g l e i n a l b i te
t w i n s v a r i e s f r o m 1 2 ~ t o I 9 ~ T h i s i s o n l y t r u e f o r
s e c t i o n s c u t p e r p e n d i c u l a r t o ( o I 0 , e x a c t l y th e k i n d
o f m i s t a k e t h a t s t u d e n t s m a k e w h e n f i rs t u s i n g
t h e M i c h e l- L 6 v y m e t h o d t o d e t e r m i n e f e ld s p a rs .
A n o t h e r v e r y m i s l ea d i n g s ta t e m e n t i s th a t ' a m o n g
t h e m e m b e r s o f th e t o u r m a l i n e g r o u p s c h o r li t e
s h o w s t h e s t r o n g e s t a b s o r p t i o n n o r m a l t o t h e
p l a n e o f t h e p o l a r iz e r '. T h e r e i s n o e x p l a n a t i o n o f
a n o m a l o u s i n t e r f e r e n c e c o l o u r s .
T h e s t a n d a r d o f p r o d u c t i o n o f t h e b o o k i s
g e n e r a l ly g o o d , w i t h t h e e x c e p t i o n o f t h e p h o t o -
m i c r o g r a p h s , m o s t o f w h i c h a r e o u t o f f o c u s a n d
u n r e c o g n i z a b l e . T h e r e a r e v a r i o u s e r r o r s o f sp e l l i n g
a n d i n d e x i n g , a n d t w o f i g u re s (4 - t 2 a n d 4 - 1 3 a) h a v e
h a d t h e i r c a p t i o n s t r a n s p o s e d . T h e i n t e r f e r e n c e
c o l o u r c h a r t i s o f v e ry p o o r q u a l it y . T h e m o s t
u s e fu l p a r t o f th e b o o k i s th e s h o r t s e c t i o n o f
d e t e r m i n a t i v e t a b l e s i n w h i c h m i n e r a l s a r e c l a s s i -
f i ed a c c o r d i n g t o t h e i r v a r i o u s o p t i c a l p r o p e r t i e s .
A . HALL
A nth on y ( J . W. ) , W i l l i a m s ( S. A . ), a nd B id e a ux
(R. A.). Mineralogy of Arizona T u c s o n , A r i z o n a
( U n i v . o f A r i z o n a P r e s s ), ~ 9 7 7 . v i i i + 2 2 5 p p . , 5 0
f igs ., 69 co lou r ph oto s . P r ice 22-5o (c lo th) , 9 '75
(paper ) .
A f t e r a n i n t r o d u c t i o n , t h i s b o o k o p e n s w i t h a
s e r ie s o f a l l - t o o - b r i e f v e r b a l s k e t c h e s o n A r i z o n a
s p e c i a li t ie s , p r i d e o f p l a c e i n t h i s c o p p e r - m i n i n g
s t a te b e i n g g i v en t o m i n e r a ls o f t h e p o r p h y r y
c o p p e r a n d r e l a t e d d e p o s i t s , f o l l o w e d b y t h e
C o l o r a d o P l a t e au - t y p e u r a n i u m a n d v a n a d i u m d e -
p o s i t s . D e s c r i p t i o n s o f t h e m i n e r a l o g y o f t h e
M a m m o t h - S t . A n t h o n y m i n e a t T i g e r a n d o f t h e
m i n e s a t B i s b e e a r e i n t e n d e d t o f i ll a g a p i n t h e
m i n e r a l o g i c a l l i t e ra t u r e . S p e c i a l r e fe r e n c e i s a l s o
m a d e t o t h e h y d r a t e d s u l p h a t e m i n e r a ls f o r m e d b y
a m i n e f i r e i n I 8 9 4 a t t h e U n i t e d V e r d e m i n e a n d
t h e r e is a n o t e o n A r i z o n a m e t e o r i t e s . B u t a f t e r t h a t
c l e a r i n g o f t h e t h r o a t , a s i t w e r e , t h e r e m a i n d e r o f
t h e b o o k i s d e v o t e d t o a n a l p h a b e t i c a l ly a r r a n g e d
c a t a l o g u e o f A r i z o n a m i n e r a l s - - t o t a l l i n g o v e r 6o o
s p e ci e s, 22 4 o f t h e m r e c o g n i z e d s i n c e t h e i 9 5 9
e d i t i o n o f Minerals of Arizona b y G a l b r a i t h a n d
B r e n n a n , a n d i n c l u d i n g 4 8 m i n e r a l s p e c i e s f i r s t
d e s c r i b e d f r o m A r i z o n a . T h i s l i s ti n g i s f o l lo w e d b y
a n e x t e n si v e b i b l i o g r a p h y a n d d e t a i le d m a p s o f
A r i z o n a m i n i n g d i s t r i c t s .
I n t h e c a t a l o g u e , t h e c h e m i c a l c o m p o s i t i o n o f
e a c h m i n e r a l i s g i v e n , t o g e t h e r w i t h n o t e s o n i t s
p a r a g e n e s i s a n d a l i s t o f l o c a l it i e s , b u t f ew o t h e r
d e t a i l s ( e v en c o l o u r ) a r e a d d e d . S o m e o f t h e e n t r i es
a r e a c c o m p a n i e d b y m o r p h o l o g i c a l d r a w i n g s a n d
t h e r e i s a g o o d l e a v e n i n g o f g e n e r a l l y e x c e l le n t
I67
c o l o u r p h o t o g r a p h s o f l o c a l iz e d m a t e r i a l ; u n f o r -
t u n a t e l y n o s c a le s a r e g i v e n a n d o n l y b y i n t u i t i o n o r
e x p e r i e n c e i s t h e r e a d e r a b l e t o j u d g e t h a t t h e
c r y s t al o f w i c k e n b u r g i t e re p r o d u c e d I c m a c r o s s is
p r o b a b l y m u c h s m a l l e r a n d t h a t t h e p ri s m a t i c
c r y s ta l s o f d i o p t a s e o r o f b r o e h a n t i t e a r e r e a l ly
i n c r e d i b l y t in y . N e v e r t h e l e s s t h i s i s a n a t t r a c t i v e
a n d u s e f u l w o r k a n d i n t h e p a p e r b a c k v e r s i o n i s
s u r e l y g o o d v a l u e . R . A . H O W l E
H ill (C. A). Cav e Minerals H u n t s v i l l e (N a t . S p e l e o -
log ica l Soc .) , I976 . I36 p p. , IO8 figs. , 9 col ou r p ls .
A v a i l a b l e f r o m N a t i o n a l S p e l e o lo g i c a l S o c i et y ,
C a v e A v e n u e , H u n t s v i l l e , A l a b a m a 3 5 8 I o ,
U . S . A . P r i c e 25 -oo ( pos tpa id ) .
T h i s a t t r a c t i v e a n d l i b e r a l l y i l l u s t r a t e d b o o k i s o n e
o f v e r y f e w t o s u r v e y t h e f i e l d o f m i n e r a l s f o u n d i n
c a ve s . S o m e s e v e n t y m i n e r a l s a r e l i s t ed a n d d e -
s c r i b e d a c c o r d i n g t o t h e u s u a l g r o u p i n g s o f c a r-
b o n a t e s , s u l p h a t e s , e t c . T h e a u t h o r a d m i t s t o
h a v i n g h a d s o m e d i f f i cu l t y i n d e f i n i n g a ' ca v e ' , a n d
t h u s a c ~ iv e m i n e r a l , a n d a n u m b e r o f t h o s e l i s t e d
h a v e b e e n f o u n d o n l y i n l ar g e vu g s i n h y d r o t h e r m a l
v e i n s o r i n w e a t h e r e d z o n e s a b o v e o r e b o d i e s .
P r e c e d e n c e i s n a t u r a l l y g i v e n t o t h e m a n y v a r ie t i es
o f c a v e c a l ci t e a n d a r a g o n i t e, a n d t h e a u t h o r d r a w s
a t t e n t i o n t o p r o b l e m s in e x p l a i n i n g h o w s o m e o f
t h e b i z a r r e f o r m s g r o w . R e f e r e n c e is a l s o m a d e t o
t h e c o n f l i c t i n g e v i d e n c e a s t o w h a t c a u s e s c a l c i t e t o
p r e c i p i t a t e i n o n e c a v e w h i l e a r a g o n i t e f o r m s i n
t h e o n e n ex t d o o r u n d e r a p p a r e n t l y t h e sa m e
e n v i r o n m e n t a l c o n d i t i o n s .
T h e r e a r e s o m e o d d i t i e s i n t h e b o o k : b a r y t e i s
s e p a r a t e d f r o m t h e r e s t o f t h e s u l p h a te s a n d n o t e d
a m o n g ' o r e - a s s o c i a t e d ' m i n e r a l s . C r i s t o b a l i t e is
c o n s i s t e n t l y m i s - s p e l t . A n o t h e r i s t h e i n c l u s i o n o f
' p e t r o m o r p h s ' , d e f i n e d a s ' s e c o n d a r y m i n e r a l d e -
p o s i t s i n t h e b e d r o c k a c c i d e n t a ll y e x p o s e d w i t h in a
c a v e ': a n e x a m p l e is th e b o x w o r k o f s m a l l q u a r t z
v e in s i n W i n d C a v e , S o u t h D a k o t a . M a n y o f th e
o t h e r c a v e m i n e r a l s li s t e d c o u l d c o m e w i t h i n t h i s
c a t e g o r y b u t t h e y a r e n o t s o n o t e d .
F o r m u l a e a r e g i v en f o r m o s t m i n e r a l s li s te d , b u t
l i t tl e i s s a id o n c r y s t a l l o g r a p h y , i n c o n t r a s t t o t h e
c o m p a r a b l e r e c e n t w o r k b y W . B . W h i t e , w h i ch t h i s
r e v i e w e r e d i t e d n o t s o l o n g a g o ( C h a p t e r 8 i n T . D .
F o r d a n d C . H . D . C u l l i n g f o r d , I 9 7 6. The Science of
Speleology A c a d e m i c P r e s s) .
L o c a l i t y i n f o r m a t i o n i s d e l i b e r a t e l y s p a r s e , a s t h e
a u t h o r e m p h a s i z e s , b e i n g l a r g e l y r e s t r i c t e d t o
t o u r i s t a n d o t h e r c o n t r o l l e d ca v e s in t h e U n i t e d
S t a t e s s o a s t o m i n i m i z e c o m m e r c i a l c o l le c t i n g a n d
o t h e r f o r m s o f v a n d a l i s m .
A s h o r t c h a p t e r a t t h e e n d r e v i e w s m a t t e r s s u c h
a s s p e l e o t h e m d a t i n g , t h e r o l e o f m i c r o - o r g a n i s m s ,