f . v i o j s o
The Mining Magazine
M anaSing Director an d E d it0r : W .F . W h i t e. A s sista n ts: St. J . R .C . Sh e p h e r d, A .R F. Hi g h a m, A .R .S.M ., M .Sc., F.G .S.
P u b l i s h e d o n t h e 1 5 t h o f e a c h m o n t h b y M i n i n g P u b l i c a t i o n a t S a l i s b u r y H o u s e , L o n d o n , E .C . 2.
Telephone ■■'Metropolitan 8938. _ Telegraphic A ddress: Oligoclase. C o d es: MeNeiU,,^ o t h ^ ^ Branch Of f ic e s/ N ew Y o rk : Amer. In s t. M. & M .E.
V Chicago : 360, N . M ichigan Blvd. S u b s c r i p t i o n j u ¿ X , $3 p e r a m
Vol. XL1II. No. 1 L O N D O N , JULY, 1930.
C O N T E N T S
9 PA G E Ed i t o r i a l
N o te s ... 2
The P etro leu m In d u stry ; M etal C rystals ; A F o rth com ing Congress ; E a st African U nion : New S cholarships a t th e R oyal School of Mines.
T h e R o y a l S chool of M ines D in n e r . . 2
Speeches a t th is a n n u a l fu n ctio n discussed.
T h re e E u ro p e a n G a th e rin g s ... 3
T he program m es of th ree rece n t congresses are o u tlin ed .
T h e I n s titu t io n ’s A n n u a l M e e tin g 4
Proceedings a t th e th irty -n in th a n n u a l m eetin g of the In s titu tio n of M ining an d M etallurgy briefly d escrib ed .
T h e O rig in of th e R a n d G o l d ... 5
A rece n t p ap e r revives th e discussion of th is m uch- d isp u te d question.
Re v i e w o f Mi n i n g... 6 Ar t i c l e s
T h e E s tim a tio n of S m a ll Q u a n titie s of T in .../ . E . Clennell T h e T h ird (T rie n n ial) E m p ir e M ining
a n d M e ta llu rg ic a l C o n g r e s s ... 13
J o h an n esb u rg to R h o d esia an d th e R etu rn .
T h e P e tr o le u m I n d u s tr y
H en ry B . M iln e r
T he au th o r sum m arizes th e p resen t po sitio n of the in d u s try th ro u g h o u t th e w orld.
T h e E a r th - R e s is tiv ity M ethod of E le c tr ic a l P ro sp e c tin g
E . L ancaster-Jones
(Concluded Jrom the J u n e issu e, p . 355.) Bo o k Re v i e w s
B n u t r v ’s " L e s M é t h o d e s G é o p h y s i q u e s d e p r o s p e c t i o n A p p l i q u é e s
d u P é t r o l e ” CarJ t. ' S h a w T r a i n ’s " L e s M é t h o d e s G e o p h y S lq u e s L ’é t u d e C o u c h e s S u p e r f i c i e l l e s d u
P ° “ I, Capt. H . Shaw
S o l ...
L E T T E R S T O T H E E D I T O R
T h e F u tu r e of th e R a n d
D r. C. B a rin g Horwood Thp E d u c a tio n of th e E n g in e e r
E rnest R . W oakes L eonard G. B row n
1 9
29
3 0
3 2 t f E w s Le t t e r s
Jo h a n n esb u rg ... 3 2
T h e P r o s p e c t i n g Concession in S. R h o d e s ia ; Life of
G o l d M ining I n d u s tr y ; Tenders for Lease Area
C l a i m s ; N o rth ern R hodesian Coal ; S outh African M ining Engineers.
PA G E
B risb a n e ... ^
A u stralian M ining ; T he W hitw orth- C om pany ; M ount Isa Progress ; Prom ising Gold D iscovery ; Q ueens
la n d ’s M ineral O u tp u t; O il Prospecting.
V a n c o u v er ... • 34
A nyox ; T he K o o te n a y s ; B o u n d a r y ; S tik in e R iver D is tr ic t; P o rtla n d Canal.
T o ro n to ...
S u d b u ry D is tr ic t; Porcupine ; K irkland Lake ; C o b a lt;
P a tric ia D is tr ic t; M anitoba.
C a m b o r n e ... ...
T he P rice of T in ; E fiects on P osition of Mines ; J a n ta r ; M ount W ellington.
Pe r s o n a l ...
3 6
3 8
... 3 9 Tr a d e Pa r a g r a p h s ... 4 0
A ndrew s H y d ra u lic Classifier ... 40 O re n stein a n d K oppel D iesel L ocom otives 42 Me t a l Ma r k e t s... 4 3 St a t i s t i c s o f Pr o d u c t i o n... 4 5 Pr i c e s o f Ch e m i c a l s ... 4 7 Sh a r e Qu o t a t i o n s ... 4 8 1 7 Mi n i n g Di g e s t
E le c tro s tra tic P re c ip ita tio n of B u rn e r Gas Im p u ritie s ...J . J . H ealy 49 T h e P re sid io M ine, T ex as
V . D . Howbert and R . Bosustow 51 D redge S c re en in g ... O. B . W illia m s 55 F lo ta tio n of W ilu n a A n tim o n ia l Ore
W . G. Clarke and B . H . Moore 58 H y d ro -m eta llu rg y of C opper
A . E . D rucker and C. F . Floe 59 T re a tm e n t of L ow -G rade S u lphide Ore
fro m th e L ak e V iew a n d S ta r M ine
W. G. Clarke and B . H . Moore 60 In c lin ed Top-Slicing ... F . M . N orris 61 Sh o r t No t i c e s ... 61 Re c e n t Pa t e n t s Pu b l i s h e d
Ne w Bo o k s, Pa m p h l e t s, e t c.
6 2 6 2 3 1 Co m p a n y Re p o r t s... 6 3 A ram ayo de Mines en B olivie ; C yprus A sbestos ; Ipoh T in D re d g in g ; K e n t (F.M.S.) T in D re d g in g ; Libiola C o p p e r;
N arag n ta K aram a A reas ; Poderosa ; S outh K algurli ; T a q u ah a n d Abosso ; T ran sv aal Gold M ining E states.
Di v i d e n d s De c l a r e d... 6 4 Ne w Co m p a n i e s Re g i s t e r e d... 6 4
EDITORIAL
I
N th is issue a s u m m a ry of o p e ra tio n s in c o n n e x io n w ith th e p e tro le u m in d u s try is given, w h ich w ill d o u b tle ss p ro v e of in te r e s t.F u r th e r in fo rm a tio n on th is s u b je c t w ill be p u b lis h e d fro m tim e to tim e as a n d w hen i t b ecom es av a ila b le .
W
E h a v e h a d o cc asio n to c o m m e n t b efo re o n th e w o rk w h ic h S ir H a ro ld C a rp e n te r is d o in g in h is rese a rc h e s in to th e in te r io r s tr u c tu r e of m e ta ls a n d in p a rtic u la r in to th e p ro p e rtie s of single c ry sta ls. I t is th e re fo re of in te r e s t to p la c e on re c o rd t h a t h e h a s la te ly c o n trib u te d f u rth e r to o u r k n o w led g e of th e s u b je c t in a p a p e r befo re th e R o y a l I n s titu t io n d e liv e re d on M ay 30.T h is is in th e n a t u r e of a re v ie w of a ll th e w o rk d o n e b y v a rio u s in v e s tig a to rs to d a te .
A
N O T H E R congress is fo rth c o m in g , th is tim e a t S to ck h o lm , w h ere from A u g u st 15 to 23 w ill b e asse m b le d th e f o u rth g en e ral m e e tin g of th e I n te r n a tio n a l U n io n for G eodesy a n d G eophysics. P a p e rs w ill b e r e a d on all a s p e c ts of th e s e su b je c ts, in c lu d in g o cean o g ra p h y , m e te o ro lo g y , a n d v o lcan o lo g y . A n e x h ib itio n of g e o p h y sica l in s tru m e n ts a n d p r a c tic a l su rv e y re s u lts is to be h e ld in c o n n e x io n w ith th e m e e tin g a n d a n u m b e r of ex c u rsio n s a re p la n n e d to p laces in S w eden w h ere finds h a v e b ee n m a d e b y th e se m e th o d s .T
H E G o v e rn m e n t h a s p u b lis h e d d u rin g th e p a s t m o n th th e conclusions w hich h a v e b e e n re a c h e d w ith re g a rd to closer u n io n in E a s t A frica. E x c e p t for som e po ssib le in d ire c t effects th e se h a v e little to do w ith th e m in in g in d u s tr y , so t h a t th e re is no n e c e s sity to q u o te fro m th e W h ite P ap ers.I t is of in te r e s t, h o w ev e r, to re c o rd t h a t th e p ro p o sa ls m e e t w ith co n sid e ra b le o p p o sitio n o n a c c o u n t of th e ir in siste n c e on th e p a ra - m o u n c y of th e n a tiv e in te re s ts , w h ich is fe lt to b e ta n ta m o u n t to re g a rd in g th e w h ite s e ttle r as a n in tr u d e r.
T
H E B ritis h S o u th A fric a C o m p an y , to g e th e r w ith th e R h o d e sia n A nglo- A m e ric a n a n d th e B w a n a M ’K u b w a C opper M ining C o m p an y , h a v e r e c e n tly a w a rd e d tw o sc h o la rsh ip s a t th e R o y a l S chool of M ines for g r a d u a te s in m in in g of t h a t S chool to ta k e a f u r th e r y e a r in m in in g geology. T h e tw o se le c te d s tu d e n ts h a v e a lre a d y s ta r t e d for a v a c a tio n to u r of th e m in in g fields s itu a te din th e P re -C a m b ria n reg io n of C a n a d a , fro m w hich to u r th e y will r e tu r n to b eg in th e n e x t session in O cto b e r. I n a d d itio n , th e tw o c o m p a n ie s m e n tio n e d , w ith th e R h o d e sia n Congo B o rd e r C oncession, h a v e m a d e a rr a n g e m e n ts for se v en sc h o larsh ip s of £100 a y e a r ea ch of fo u r y e a r s ’ d u r a tio n to assist b o y s fro m se lec ted p u b lic schools to ta k e th e fo u r y e a r s ’ course a t th e R o y a l S chool of M ines b eg in n in g in O cto b e r, 1930.
T h e R o y a l S c h o o l o f M in e s D in n e r T h e 5 3 rd A n n u a l D in n e r of th e R o y a l S chool of M ines, u n d e r th e a u sp ice s of th e O ld S tu d e n ts ’ A sso c iatio n , w as ju s t su c h a h a p p y fa m ily g a th e rin g a s u su a l a n d m a n y fa m ilia r faces w ere seen. T hose w ho w ere a t th is fu n c tio n e x a c tly a y e a r b efo re w ill p r o b a b ly re m e m b e r t h a t one of th e s a lie n t fe a tu re s of th e speeches w as th e e x is tin g s h o rta g e of m e n of th e r ig h t ty p e fo r m in in g en g in ee rin g . T h is w as also th e m a jo r to p ic a t th is y e a r ’s d in n e r. D r.
W illia m C ullen, w ho p ro p o se d th e to a s t of th e S chool for th e second y e a r in succession (is th is a re c o rd ?), ra ise d th e s u b je c t b y re fe rrin g to a le tte r r e c e n tly p u b lis h e d in th e T im e s b y th e P ro fe sso r of M in in g a t B irm in g h a m U n iv e rs ity — a le tte r w h ic h h a s o ccasioned, r ig h tly o r w ro n g ly , a good d ea l of ir rita tio n . D r. C ullen is o f o p in io n t h a t one of th e m o s t p o w e rfu l d e te r r e n ts to e m b a rk in g on th e p ro fessio n of m in in g e n g in ee rin g is th e fe a r of p h th is is . T h is is p r o b a b ly tr u e of S o u th A frica, w h ile th e fa c t t h a t th e m e d ic a l re s tr ic tio n s a re sev ere p ro b a b ly p r e v e n ts m a n y p a r e n ts in th e h o m e c o u n try fro m s ta r t in g th e i r sons on a n ex p e n siv e co u rse of tr a in in g w h ic h m a y o n ly c u lm in a te in th e ir b e in g re je c te d a s u n fit for d u ty , n o t o n ly on th e R a n d b u t else
w here. I t h a s to b e b o rn e in m in d , to o , t h a t p rio r to th e b eg in n in g of th e p re s e n t in te n siv e d e v e lo p m e n t in N o r th e r n R h o d e sia th e m in in g in d u s tr y of th e E m p ire w as in a v e r y d ep re sse d c o n d itio n a n d th e re w as th e re fo re little in d u c e m e n t fo r m e n to e n te r it. T h is a p p a r e n t w a n t of e n te rp ris e in y o u n g m e n m a y also b e d u e to th e in c re a s e d a t tr a c t iv e ness of co m m ercial life a t hom e, as d isc u sse d h ere a n e n t th is d in n e r a y e a r ago.
F ro m e x a m in in g th e m a la d y D r. C ullen w e n t on to co n sid e r a c u re a n d w as d isp o se d to m a k e a c o m p ariso n b e tw e e n th e U n iv e rs ity of th e W itw a te rs ra n d a n d th e m in in g tr a in in g in s titu tio n s in th is c o u n try . In th e fo rm e r th e re w as u n til re c e n tly a big
J U L Y , 1930 3
fallin g off in s tu d e n ts , as in th e la tte r , b u t as a re s u lt of som e ch an g e in th e c u rric u lu m , r e s u ltin g in th e d e v o tio n of m ore fo u rth - y e a r tim e to p r a c tic a l ex p e rien c e w ith p a y — a s re c o rd e d b y o u r Jo h a n n e s b u rg co rre
s p o n d e n t in tiiis issue— th e n u m b e rs h a v e b ee n in c re asin g co n sid erab ly . I t w as n o t n ec essary for a p ro ta g o n is t of th e R o y a l S chool of M ines to c o n te st th is pro p o sal, a n y m o re th a n it is n o w n ec e ssa ry for th e Ma g a z i n e to do so, b ecau se a la te r sp e ak e r a t th e d in n e r— Mr. W . E . W a in w rig h t, th e p re s id e n t of th e A u s tra la s ia n I n s titu te of M ining a n d M e tallu rg y — u tte r e d a sp irite d p le a for “ le av in g th e f o u rth y e a r a lo n e .”
W e en d o rse h is o p in io n for th e reaso n t h a t th e co u rses in m in in g a n d m e ta llu rg y being w ide in th e ir scope do n o t a d m it of a n y c o n tra c tio n . T h e re is, to o , p le n ty of tim e in th e v a c a tio n s for o b ta in in g p ra c tic a l tr a in in g if o n ly th e facilities w ere av ailab le.
I t is n o t a lto g e th e r re a so n a b le to m a k e an a lo g ie s b e tw e e n th is c o u n try a n d A m erica, C a n ad a , a n d S o u th A frica, b ecause th e c a rd in a l fa c t re m a in s t h a t in G re a t B rita in th e re a re no m e ta l m ines a n d m e ta llu rg ic a l w o rk s c o m p a ra b le w ith th o se in th e o th e r c o u n trie s n a m ed . Mr. E . H alse re p lie d to th e to a s t a n d , as h is m e m o ry goes b a c k to th e p e rio d 1873-6, w h en h e w as a s tu d e n t, he w as a b le to in d u lg e in som e in te re stin g rem iniscences. O th e r sp e a k e rs w ere M ajor H e n d e rso n -S c o tt, w ho p ro p o sed th e gu ests, a n d Mr. C harles M cD erm id, w ho rep lied , w h ilst Mr. E . T . M cC arth y p ro p o sed th e c h a irm a n , w ho w as a c o n te m p o ra ry w ith h im a t th e School.
T h e re is one o th e r p o in t d e a lt w ith b y th e p rin c ip a l sp e ak e r w hich m e rits special a tte n tio n . H e m a d e a p le a for som e form of co nference b etw e e n th e le ad e rs in th e in d u s try a n d e d u c a tio n ists. M any critics m a y b e d isp o se d to ex p re ss th e op in io n t h a t conferences “ g e t y o u n o w h e re .” Be t h a t as it m a y , th e re is n o g ain say in g th e fa c t t h a t som e closer lia iso n b etw een th e te c h n ic a l a n d o th e r le ad e rs in th e in d u s try a n d , sa y , th e R o y a l S chool of Mines w ould b e a d v a n ta g e o u s to b o th . T h is b rin g s us a g a in to th e a ll-im p o rta n t q u e stio n of how to su p p le m e n t th e p r a c tic a l tra in in g a t p re s e n t a v a ila b le to s tu d e n ts in th is c o u n try . H e re th e in d u s try c a n defin itely h e lp b y affo rd in g o p p o rtu n itie s to y o u n g m e n in th e ir second a n d th ir d y e a rs of w o rk in g on p ro p e rtie s w hich, a lth o u g h n e a r hom e, m a y be b e y o n d th e m e an s of th e a v e rag e s tu d e n t to re a c h in h is v a c a tio n tim e. A d d itio n a l fac ilities for p o s t-g ra d u a te w o rk in m ines
f u rth e r afield sh o u ld also becom e a v a ila b le . T h is is a d u ty w hich th e in d u s try owes to such in s titu tio n s as th e R o y a l School of M ines. I t m a y be sa id t h a t such facilities do ex ist, b u t is th e re n o t som e n ecessity to increase th e m ? T h e selection of m en for such “ sc h o larsh ip s ” o r “ tra v e llin g fellow ships ” sh o u ld also b e on all-ro u n d m e rit r a th e r th a n solely on academ ic a tta in m e n ts , follow ing th e o ft-q u o te d rea so n in g t h a t th e b e s t s tu d e n t does n o t n ecessarily m a k e th e b e s t engineer. Mr.
W a in w rig h t ca rrie d th is suggestion a stage f u rth e r b y re m in d in g u s of th e sy stem in vogue in A u stra lia w h ereb y c e rta in big m in in g com panies secu re y o u n g m en before g ra d u a tio n a n d in itia te th e m on th e p ro p e rtie s d u rin g v a c a tio n tim e, su b se q u en tly g iv in g th e m em p lo y m en t.
T h r e e E u r o p e a n G a t h e r in g s T h e C o n tin en t w itn e ssed tw o im p o rta n t conferences la st m o n th each of w hich a ttr a c te d th e a tte n tio n of m in in g m en, w hile a th ir d , of in te re s t to th e geological c o m m u n ity , h a s ju s t concluded. T he Second W o rld P ow er Conference, held in B erlin from J u n e 15 to 25. w as a tte n d e d b y d elegates from no few er t h a t 55 cou n tries, am ong w hom w ere se v eral p ro m in e n t in m ining. I t will be recalled t h a t th e first conference w as held a t W em bley in 1921, w hile sectional m e etin g s h a v e in th e in te rim b een held a t B ale, L ondon, B arcelona, a n d T okio. I t is b eyond th e pro v in ce of th e Ma g a z i n e to e n te r in to d e ta ils concerning th is conference, b u t one circ u m sta n ce reg a rd in g it deserves to be p laced on record. N a tu ra lly m o st of th e p ap e rs a n d th e discussions th e re o n were in th e G erm an language, b u t d elegates of o th e r co u n tries n o t fam iliar w ith th is to n g u e ex p erien ced no difficulty in follow ing th e p roceedings b y reason of th e ela b o ra te in te rp re tin g arra n g e m e n ts av a ila b le for tra n s la tin g in to e ith e r F re n c h or E nglish.
I n each of th e th re e h alls in w hich sessions w ere h eld th e s p e a k e r’s ro s tru m w as fitte d w ith a m icrophone co n n ected to h ea d te lep h o n e sets a t th e in te r p re te rs ’ ta b le . T h e in te rp re te rs in tu r n w ere able to tr a n s m it b y m ean s of o th e r m icrophones in one of th e th re e languages, each se a t in th e a u d ito riu m bein g eq u ip p e d w ith h ea d p h o n es a n d ch an g e
o v er a n d v o lu m e -co n tro l sw itches. E x c e p t for a slig h t tim e lag in th e case of those tr a n s m itte rs w ho h a d to tra n s la te from th e sp e a k e r’s language, th e sy ste m w o rk ed well on th e w hole.
T h e se co n d co n feren ce in ch ro n o lo g ical o rd e r w a s th e S ix th I n te r n a tio n a l C ongress of M ining, M e ta llu rg y , a n d A p p lie d G eology, h e ld a t L iège fro m J u n e 22 to 28, w h ich , a s i t is of m o re d ir e c t in te r e s t to re a d e rs, m a y b e d e a lt w ith m o re fu lly . I n th is case th e p re v io u s m e e tin g w as h e ld a t D ü sse ld o rf in 1910 a n d t h e n e x t sh o u ld h a v e b e e n h eld in 1915, b u t h o stilitie s, of course, p re v e n te d it.
A d v a n ta g e w as, th e re fo re , ta k e n of th e B e lg ia n n a tio n a l c e le b ra tio n s on th e occasion of th e c e n te n a ry of t h a t c o u n tr y ’s in d e p e n d en ce to h o ld th e p re s e n t session th e re a n d in co n n e x io n w ith th e Liège a n d A n tw e rp E x h ib itio n s . D u rin g th e p e rio d m e n tio n e d th e m o rn in g s w ere for th e m o s t p a r t g iv e n u p to te c h n ic a l sessions, th e a fte rn o o n s to v isits to m ines, w o rk s, o r places of geological in te r e s t, a n d th e ev en in g s to e n te rta in m e n ts , w h ich th e h o sts w ere m o st la v is h in p ro v id in g . C o n g ra tu la tio n s for th e o rg a n iz a tio n are e sp ec ially d u e to P ro fesso r F o u rm a rie r, of th e U n iv e rs ity of Liège, for h is able p re sid e n c y , a n d to Mr. O. L ep e rso n n e for h is e q u a lly c re d ita b le se c re ta ry -g e n e ra lsh ip . P a p e rs in th e m in in g se c tio n d e a lt w ith all a s p e c ts of th e s u b je c t in b o th coal a n d m e ta l m in in g , w h ile th e m e ta llu rg y se ctio n c o v e red b o th th e fe rro u s a n d n o n -fe rro u s.
I n geology w as in c lu d e d a geophysics sectio n . A ll th e se sessions w ere p a rtic u la rly w ell a tte n d e d b y d eleg a tes fro m th e c o u n trie s r e p re s e n te d a n d a lth o u g h th e la n g u ag e d iffic u lty w as a b a r r ie r i t w as n o t a n in s u r
m o u n ta b le one. A m o n g th e p laces v isite d p a r tic u la r m e n tio n m a y b e m a d e of th e m a n g a n e se m in es of th e V allée de la L ien n e, th e lim e sto n e g allerie s a t N éb lo n , th e w o rk s o f th e V ieille M o n ta g n e a t b o th C alam ine a n d B aelen , a n d th e e le c tro ly tic co p p e r re fin e ry of th e U n io n M inière a t O olen.
T h e th ir d conference re fe rre d to w as th e c e n te n a ry c e le b ra tio n of th e F re n c h G eo
lo gical S ociety , h e ld in P a ris, w h ich w as also a tte n d e d b y d eleg a tes fro m m a n y c o u n trie s. T h is a g a in w as a n occasio n for te c h n ic a l sessions, m a n y e x c u rsio n s o v er a w ide field, a n d so cial e n te r ta in m e n ts , to w h ich a n u m b e r of p eo p le p assed on fro m Liège.
I t is p ro p o se d to give a b rie f d e s c rip tio n of th e e x h ib itio n s a t A n tw e rp a n d Liège in th e n e x t issue of th e Ma g a z i n e, b u t it m ig h t b e a d d e d h e re t h a t a fo rm a l d ecision w as m a d e a t th e closing session in L iège to h o ld th e n e x t I n te r n a tio n a l C ongress in F ra n c e in 1935, in v ita tio n h a v in g b ee n fo rm a lly e x te n d e d on b e h a lf of th e in te re s ts co n ce rn e d .
T h e I n s t i t u t i o n ’s A n n u a l M e e t in g P a r tic u la r in te r e s t a tta c h e d to th is y e a r ’s m e e tin g of th e I n s titu tio n , b ec au se th e r e p o r t of th e C ouncil fo r th e y e a r ju s t co n c lu d e d co n ta in s th e first official d e ta ile d in fo rm a tio n co n c ern in g th e new h o u sin g p ro p o sa ls for m e m b ers. T h e re w as, h o w ev e r, a n o th e r re a so n for sp e cia l in te re s t in th is m e etin g , t h a t S ir T h o m a s H o lla n d w as to b e p re se n te d w ith th e G old M edal. T h is a w a rd w as d e s e rv e d ly p o p u la r, for S ir T h o m a s h a s se rv e d th e I n s titu tio n w ell b o th a s p re s id e n t for tw o successive y e a rs a n d as a n a c tiv e m e m b e r of th e C ouncil for se v e ra l m o re, w h ilst h is p u b lic services as D ire c to r of th e G eological S u rv e y of I n d ia a n d as R e c to r of th e Im p e ria l College a re w ell k n ow n.
D r. W illia m C ullen p e rfo rm e d one of h is la s t a c ts as p re s id e n t in m o v in g th e a d o p tio n of th e a n n u a l r e p o r t a n d re fe rre d to th e success of th e C ongress in S o u th A fric a , follow ing th is b y a re c a p itu la tio n of th e a rg u m e n ts in fa v o u r of th e re m o v a l of th e h e a d q u a rte rs of th e I n s titu tio n fro m C lev elan d H o u se to W e stm in ste r, w h ere it w ill be jo in t te n a n ts w ith a n u m b e r of o th e r societies.
I n view of th e p re s e n t s ta te of u n e m p lo y m e n t in th e profession, D r. C ullen also fe lt it d e sira b le to in d ic a te t h a t th e fu n c tio n of th e I n s titu t io n ’s A p p o in tm e n ts (In fo rm a tio n ) R e g iste r m u s t b e confined to t h a t of a c tin g a s a clea rin g h o u se a n d p o in te d o u t t h a t th e I n s titu tio n , in v ir tu e of its C h a rte r, is p re c lu d e d fro m a c tin g as a n e m p lo y m e n t ag e n c y w h e re b y p referen c e m ig h t b e g iv e n to one m e m b e r o v er a n o th e r. T h e re p o rt a n d a c c o u n ts h a v in g b e e n a d o p te d , th e p r e s id e n t th e n p re s e n te d th e G o ld M edal to S ir T h o m a s H o lla n d , s u ita b ly re fe rrin g to h is rec o rd . S ir T h o m a s, in ac c e p tin g th e a w a rd , sp o k e of th e lo y a l c o -o p e ra tio n of h is staffs, b o th in I n d ia a n d L o n d o n , s u b s e q u e n tly d e a lin g w ith th e re fo rm of th e m a c h in e ry for th e co llectio n , co n tro l, a n d s tu d y of m in e ra l s ta tis tic s d u rin g h is la s t y e a r of office in In d ia , a s a re s u lt of w h ich in fo rm a tio n h a d b e e n g a in e d as to th e p o lic y to b e a d o p te d b y th e S u rv e y to en su re th e d e v e lo p m e n t of th e m in e ra l reso u rces of th e c o u n try . T h is also re s u lte d in th e G o v e rn m e n t fo rm u la tin g ru le s fo r th e g ra n tin g of m in e ra l concessions w h ich h a d since b ee n closely follow ed in p rin c ip le b y o th e r p a r ts of th e E m p ire . S ir T h o m a s also sp o k e of th e c irc u m sta n c e s asso c ia te d w ith th e g ra n tin g of th e B.Sc. D eg ree of L o n d o n U n iv e r s ity to A sso ciates of th e R o y a l S chool of M ines, a ch a n g e for w h ich
JU L Y , 1930 5
h e w as chiefly resp o n sib le. O th e r a w a rd s a n n o u n c e d a t th is m e e tin g w ere th o se of th e
“ C o n so lid ated G old F ield s of S o u th A frica, L t d . , ” P re m iu m of F o r ty G u in eas to Mr. J o h n B. R ic h a rd so n , th e “ W illiam F rech ev ille S tu d e n ts P riz e of T e n G u in eas to Mr. A rth u r B ra y a n d th e “ A rth u r S. D w ig h t ” P o st- G ra d u a te T ra v e llin g G ra n t of Tw o H u n d re d G u in ea s to Mr. W . D. Jo n e s, th e la s t m e n tio n e d bein g th e first such a w a rd to be m a d e . A sp e cia l g r a n t of £50 from th e
“ P o s t-G ra d u a te G ra n ts F u n d ” h a s b een m a d e to Mr. S. R . B. Cooke to e n a b le h im to p ro ce ed from N ew Z e a la n d to B ritish C olu m b ia to g a in p ra c tic a l experience.
T h e m e e tin g co n clu d ed w ith th e d eliv ery of h is p re s id e n tia l ad d re ss b y P rofessor J . G. L aw n , th e su b je c t chosen being
“ P e rio d ic a l V a ria tio n s in th e P rices of M inerals a n d M e tals.” P rofessor L aw n first d ea ls w ith th e use of m e ta ls as m o n e y , a n d review s th e v a rio u s sta g es w hich h av e led to th e p re s e n t a sce n d en cy of gold over silv er, p assin g on to a n h isto ric a l su rv e y of th e v a ria tio n s t h a t h a v e ta k e n p lace in th e p rices of som e of th e m e ta ls a n d concluding w ith a d iscussion on th e effects of c o n tro l to a ssist th e p ro d u c e r b y m a in ta in in g a sta b le a n d econom ic price. T h e p a p e r w ill u n d o u b te d ly b e r e a d w ith as m u c h in te re s t b y th o se w ho w ere n o t p re se n t as it w as h e a rd b y th o se w ho lis te n e d to it.
T h e O r ig in o f t h e R a n d G o ld T h e s to r y of th e d e v e lo p m e n t of th e gold m in es of th e T ra n s v a a l, w h ich y e a rly c o n trib u te m o re th a n h alf of th e w o rld ’s a n n u a l o u tp u t of th e precio u s m e ta l, form s one of th e m o s t w o n d erfu l c h a p te rs in th e h is to ry of m ining. T h a t a d is tric t of such im p o rta n c e to th e w orld sh o u ld h a v e been w ell s tu d ie d b y geologists of m a n y n a tio n alitie s is n o t su rp risin g , b u t it is th u s th e m ore re m a rk a b le t h a t, a lth o u g h th e d isc o v ery of th e “ b a n k e t ” w as m a d e in 1886, th e re is ev en now no u n a n im ity on th e q u e stio n of th e o rig in of th e gold it co n tain s.
T h is q u e s tio n of th e o rig in of th e gold h a s c a u se d m u c h discussion a n d as fa r b a c k as 1903 D e L a u n a y su m m a riz e d th e v ario u s h y p o th e se s a n d show ed t h a t th e re w ere th re e m a in th e o ries, w h ich a re u su a lly know n as th e p lacer, th e p re c ip ita tio n , a n d th e in filtra tio n th e o ries. T hese, in th e sam e o rd er, assu m e th e gold to h a v e b ee n d ep o site d b efo re, d u rin g , o r a fte r th e cong lo m erate its e lf h a d b ee n d ep o site d . T h e p la ce r th e o ry su p p o ses th e gold to h a v e b ee n
m e ch a n ic a lly d e p o site d a t th e sa m e tim e as th e peb b les, a ll being d eriv e d fro m th e d e n u d a tio n of p re -e x istin g a u rifero u s rocks.
T h e second th e o ry re g a rd s th e g o ld a n d p y rite as bein g ch em ically p re c ip ita te d from th e w a te r in w hich th e pebbles w ere bein g la id dow n, w hile th e s u p p o rte rs of th e in filtra tio n th e o ry h o ld th e view t h a t th e d e p o sits a re epigenetic, th e gold, to g e th e r w ith p y rite , som e q u a rtz , a n d o th e r se c o n d a ry m in erals, h a v in g b een in tro d u c e d b y ascending m a g m a tic w a te rs, th u s reg a rd in g th e m e ta l as of p o st-se d im e n ta ry origin.
T h e p re c ip ita tio n th e o ry has, p erh a p s, now b een e n tire ly a b a n d o n e d , in view of th e m a n y difficulties w h ich are in v o lv e d in its su p p o rt, a n d D u T o it h as p o in te d o u t th a t th e m a n y a rg u m e n ts a d v a n c e d in fav o u r of e ith e r of th e o th e r tw o th e o rie s can, w ith b u t slig h t m odification, be eq u a lly well ap p lied to th e o th e r, a n d t h a t th e re a re v e ry stro n g a rg u m e n ts a g a in st b o th of th e m . D u T o it re g a rd s th e c rite ria to b e as y e t indecisive to e s ta b lish th e ascen d en cy of a n y one view a n d th in k s th a t m ore evidence on crucial p o in ts is d esirable.
A t a m e etin g of th e In s titu tio n , h e ld in N o v em b er, 1928, Mr. A rth u r B ra y , in a p a p e r on th e b a n k e t d ep o sits of th e G old C oast (for w hich h e w as a w a rd e d th e W illiam F re ch e v ille S tu d e n ts P rize of th e I n s titu tio n of M ining a n d M etallu rg y )— d eposits w hich are v e ry sim ilar to th o se of th e R a n d - considered th a t all th e evidence w as in fav o u r of th e d eposition of th e gold from ascen d in g m ineralizing solutions, a view w hich w as, how ever, d isp u te d b y D r. J u n n e r in 1929, th e la tte r, to g e th e r w ith Sir A lb ert K itso n , ho ld in g th e placer th e o ry to b e th e m ore p ro b ab le. The w hole q u estio n , w hich m a y , p e rh a p s, be reg a rd e d as p u rely academ ic, b u t w hich h a s econom ic im p o rta n ce w hen th e f u tu re of th e d is tric t is considered, h a s been re-o p en e d b y P rofessor L. C. G rato n , of H a rv a rd . P rofessor G ra to n , in a p a p e r w hich is issued as a su p p le m e n t to Economic Geology for M ay, su p p o rts a h y d ro th e rm a l orig in for th e R a n d gold. T he m e th o d follow ed b y th is w rite r h a s b een to show t h a t th e fa c ts a re in c o m p atib le w ith th e d em an d s of th e h o ld ers of th e p la ce r th e o ry , w hile th e y are co m p atib le w ith th e view th a t
“ th e gold h a s b een in tro d u c e d from a d ee p -sea ted m a g m a tic source b y h y d ro - th e rm a l so lu tio n s of th e sam e k in d as h a v e p ro d u c e d m a n y of th e o th e r g re a t gold d e p o sits of th e w o rld .’ T h e a rg u m e n t of P ro fesso r G ra to n is c e rta in ly v e ry co n vincing.
REVIEW OF MINING
I n t r o d u c t io n .— P e rh a p s th e m o st im p o r ta n t e v e n t in th e C ity d u rin g th e p a s t m o n th h as b ee n th e p a ssin g of a re so lu tio n b y c e r ta in e m in e n t b a n k e rs a n d C ity m e rc h a n ts a d v o c a tin g u rg e n t m e a su re s for th e p ro m o tio n of I n te r - Im p e r ia l tra d e . I t is felt t h a t th e E m p ire is sufficiently se lf-c o n ta in e d to fo rm a single econom ic u n it a n d s u p p o r t is gro w in g for th e p olicy u n d e rly in g th e reso lu tio n . T h e p rices of m e ta ls still occasion a n x ie ty , th e f u rth e r s e tb a c k in tin b ein g d u e to la c k of u n a n im ity am o n g p ro d u ce rs, w h ilst a n o th e r d is tu rb in g f a c to r is in c re a se d u n e m p lo y m e n t.
T r a n s v a a l.— T h e o u tp u t of gold on th e R a n d d u rin g J u n e w as 847,352 oz. a n d in o u tsid e d is tric ts 40,515 oz., m a k in g a to ta l of 887,867 oz., as c o m p a re d w ith 916,213 oz.
in M ay. A t th e e n d of J u n e th e n u m b e r of n a tiv e s w o rk in g in th e g o ld m in e s w as 201,324, as c o m p a re d w ith 202,182 a t th e e n d of M ay.
T h e a c c o m p a n y in g ta b le gives th e d iv id e n d s for th e first h a lf of 1930 for th e g o ld m in es of th e R a n d a n d th e H eid e lb e rg d is tric t. T h e n o te w o r th y in c re ase is t h a t of L a n g la a g te E s ta te a n d o th e r in c re ase s a re show n b y D u rb a n R o o d e p o o rt D ee p , G e ld e n h u is D eep, a n d R ose D eep. O n th e o th e r h a n d th e re a re som e d ro p s to b e rec o rd e d . T h a t of th e N ew M o d d e rfo n te in
2nd half, 1928.
1st half, 1929.
2 nd half, 1929.
1st half, 1930.
s. d. s. d. s. d. s. d.
B ra k p a n ... 5 0 4 9 5 0 4 3
C on so lid ated M ain R e e f.. 1 1) 1 0 1 0 0 9
Crow n M ines ( 1 0 s .) ... 3 0 8 3 3 3 3 3
D u rb a n R o o d ep o o rt D eep 0 3
G eduld ... 3 H H Of 3 a t 3 3 t
G eld en h u is D eep ... 0 6 0 6 0 0 0 9
G o v ern m e n t A r e a s ... 2 8 2 3 2 3 2 3 L a n g laag te E s ta te ... 1 6 1 (3 1 ts 2 0 M o d d erfo n tein B (5 s.). . . 2 0 2 0 2 0 2 0
M odd erfo n tein D eep (5s.) 3 0 3 3 3 (3 3 3
M odd erfo n tein E a s t . . . . 2 0 2 0 2 0 2 0
M odderfontein, N ew (10s.) 7 0 Y 0 V 0 13 9
N ew S ta te A reas ... 1 0 1 6 1 0 1 (3
N ourse M ines ... 0 (1 0 0 0 b
R o b in so n D eep (A. Is.) . 1 6 1 (3 1 (3 1 0
Rose D e e p ... 0 (3
S p rin g s M in es... 8 Ö 3 0 3 9 3 b
Sub N igel (10s.) ... 8 0 2 0 2 0 2 0
V an R y n ... 0 0» 0 ts* 0 b* 0 b*
V an R y n D e e p . . . . 4 0 3 (3 3 0 3 0 V illage D e e p ... 0 0 0 6 0 b 1 W e st S p r i n g s ... 1 0 1 0 1 0 1 0
W itw a te rs ra n d Gold . . . 0 0 1 0
* T a x free. t On in creased c a p ital.
X M ine now ow ned b y R o b in so n Deep.
w as e x p e c te d so o n e r o r la te r , p e rh a p s, as it h a s beco m e n e c e ssa ry to t r e a t a la rg e r p o rtio n of low er g ra d e ore fro m th e u p p e r
le a d e rs a n d s o u th reef, a n d in th e case of th e V an R y n D eep th e la s t a n n u a l r e p o r t sh o w ed a slig h tly re d u c e d g ra d e of o re re se rv e s as w ell as re d u c e d e a rn in g s. T h e less fa v o u ra b le d e v e lo p m e n ts a t th e B r a k p a n h a d also fo re sh ad o w e d re d u c e d p ro fits.
O th e r d ecreases a re sh o w n b y C o n so lid a te d M ain R eef a n d M o d d e rfo n te in E a s t.
T h e d iv id e n d s of th e fin an ce c o m p a n ie s a re c o m p a re d below :—
1st h alf 1929.
2nd half 1929.
1st h alf 1930.
s. d. s. d. s. d.
J o h a n n e s b u rg C o n s o lid a te d ... 1 6* 1 6* 1 6 t N ew E ra C o n s o lid a te d ... 0 3 0 3 — R a n d M ines ... 2 6 2 6 2 0 R a n d S electio n ... 0 9 0 6
* T a x free. t Less ta x .
I n th e case of th e R a n d S electio n C o rp o ra tio n it h a s b e e n a n n o u n c e d t h a t th e b o a rd co n sid er i t d esira b le to h u s b a n d th e reso u rce s of th e c o m p a n y p e n d in g a n im p ro v e m e n t in b u sin e ss co n d itio n s.
A t th e a n n u a l m e e tin g of H e n d e rs o n ’s T ra n s v a a l E s ta te s , to b e h e ld th is m o n th , i t is p ro p o se d to re d u c e th e c a p ita l of th e co m p a n y fro m £1,075,000 to £860,000, a n d th e s h a re v a lu e fro m 5s. to 4s. H o ld e rs of th e 2,818,487 issu e d sh a re s w ill rec eiv e Is.
r e tu r n e d c a p ita l o n e a c h s h a re h eld . O p e ra tio n s for th e y e a r e n d e d M arch 31 la s t re s u lte d in a n e t p ro fit of £39,071, as c o m p a re d w ith £36,196 in th e p re v io u s y e a r.
A d iv id e n d of 5% w as p a id in e a c h y e a r.
A fall of ro c k in th e C o n so lid a te d M ain R eef m in e a b o u t th e m id d le of J u n e c a u s e d th e loss of se v e ra l lives.
A t th e q u a r te rly m e e tin g of th e Jo h a n n e s b u rg C h a m b e r of M ines, h e ld la s t m o n th , D r. P . M. A n d e rso n sa id t h a t , as a re s u lt of th e n ew M o zam b iq u e C o n v e n tio n , th e n u m b e r of E a s t C oast n a tiv e s e m p lo y e d on th e R a n d h a d d e c re a s e d fro m 92,000 to 78,000. H e r e ite r a te d th e v ie w t h a t th e in d u s tr y w as lik e ly to b e fac ed w ith a se rio u s s h o rta g e of n a tiv e la b o u r, a s th e s u p p ly w ith in th e U n io n its e lf w as in a d e q u a te .
S o u t h e r n R h o d e s i a . — T h e o u tp u t of gold fro m S o u th e rn R h o d e sia d u rin g M ay w as 47,645 oz., as c o m p a re d w ith 45,806 oz.
in A p ril a n d 48,189 oz. in M ay of 1929.
O th e r o u tp u ts in M ay w ere : S ilv er, 5,802 oz. ; co p p e r, 128 to n s ; coal, 90,680 to n s ; ch ro m e ore, 22,983 to n s ; a sb e sto s, 2,762 to n s ; m ic a, 19 to n s ; d ia m o n d s, 18 c a ra ts .
J U L Y , 1930 7
A c irc u la r issu ed la s t m o n th to s h a re h o ld e rs of th e G a ik a G old M ining C o m p an y , L td ., s ta te d t h a t d ev e lo p m e n ts a t th e m ine c o n tin u e to be d isa p p o in tin g . A lth o u g h ev e ry effo rt h a s b ee n m a d e to disco v er fresh ore, th e rese rv e s a re r a p id ly bein g ex h a u ste d . I t is also re v e a le d th a t n e g o tia tio n s h a v e b ee n going on for a co n sid erab le p erio d to dispose of th e m in e as a going concern or, failin g t h a t, of th e p la n t, b u t, so far, w ith o u t success. I t is e s tim a te d t h a t in th e e v e n t of liq u id a tio n sufficient assets are a v a ila b le to p e rm it of a d is trib u tio n of a t le a s t 4s.
p e r sh are.
N o r t h e r n R h o d e s ia .— T h e re p o r t of th e R h o d e s ia -K a ta n g a C o m p an y for th e p erio d e n d e d D ec em b e r 31 la st, w hich w as issued la s t m o n th , c o n ta in s a su m m a ry of progress a t th e K a n s a n s h i m ine. W o rk to d a te show s th a t, in a d d itio n to th e h ig h -g ra d e fissure v ein s w o rk e d in th e e a rly sta g e s of d ev e lo p m e n t before th e W a r th e re are larg e bodies of o th e r co p p er ores being d eveloped. T hese a re tw o la rg e re p la c e m e n t d e p o sits in th e d o lo m ite on th e e a s t a n d w est sides of K a n sa n sh i H ill a n d su lp h id e -b e a rin g beds of g ra p h ite sc h ist a n d q u a r tz ite form ing- low -grade co p p er ore-bodies of considerable th ic k n ess. D ev e lo p m e n t is bein g ad v a n c e d w ith th e o b je c t of a rriv in g a t a decision as to th e scale on w h ich o p e ra tio n s sh a ll be co n d u c te d . T h e tr e a tm e n t p la n t w ill be d esig n ed b y Mr. A. E . W heeler, w ho h a s h a d e x te n siv e ex p e rien c e w ith th e ores of th e K a ta n g a . As soon as possible a d ire c t ra ilw a y co nnexion w ill b e m a d e w ith th e B elg ian se ctio n of th e B en g u ela R ailw ay , w h ich w ill lin k th e m in e w ith th e p o r t of L o b ito on th e A tla n tic se ab o a rd .
S h areh o ld e rs of th e R h o d e sia n Congo B o rd e r C oncession h a v e b ee n in fo rm ed of new b o re-h o le re su lts. B ore-hole N .E . 26, w hich lies a p p ro x im a te ly 1,000 ft. e a s t of b o re-h o le N .E . 7 on th e w e ste rn e x ten sio n of th e N ’C h an g a a re a , e n te re d th e L ow er or R iv e r lode h o rizo n a t 593 ft. a n d to 647 ft.
th e ore a v e ra g e d 6-46% copper, of w hich 47-2% is in th e form of sulphide.
S h areh o ld e rs of R h o d e sia n A nglo A m erican, L td ., h a v e b e e n offered a f u rth e r 600,000 sh a re s p ro r a t a to th e ir holdings. T he new 10s. sh a re s a re offered a t 30s. p e r sh a re a n d w ill h a v e o p tio n rig h ts. A circ u lar issued b y th e co m p a n y s ta te s t h a t a larg e p o rtio n of th e p re s e n t cash resources w ill be re q u ire d to p ro v id e th e fu n d s n ec essary to en ab le c e r ta in N o rth e r n R h o d e sia n com panies to b e b r o u g h t to th e p ro d u c tio n sta g e a n d t h a t
th e new issue h a s b een m a d e to p ro v id e m e an s for th e a c q u isitio n of f u rth e r in te re s ts in th e sa m e field.
N ig e r ia .— A t a m e e tin g of th e N ig eria n C h a m b e r of M ines, h e ld in L o n d o n on J u l y 1, th e re c o m m e n d a tio n of th e e x e cu tiv e co m m itte e of th e T in P ro d u c e rs’ A ssociation for a tw o m o n th s ’ sh u t-d o w n of p ro d u c tio n w as en d o rsed . I t w as d ec id e d t h a t th e com p an ies o p e ra tin g in N ig eria sh o u ld re s tr ic t th e ir p ro d u c tio n over th re e m o n th s to one th ir d of th e ir av e rag e m o n th ly p ro d u c tio n in 1929.
A u s t r a lia .— T h e low p rices p re v a ilin g for le ad , zinc, a n d silv er h a v e h a d serious effects on th e B ro k en H ill g ro u p of m ines.
T o w ard s th e en d of J u n e a m e e tin g to o k p lace b etw e en re p re se n ta tiv e s of th e B a rrie r I n d u s tria l C ouncil a n d th e S u lp h id e C orp o ra
tio n , B ro k en H ill P ro p rie ta ry , a n d B lock 14 to consider th e sugg estio n of th e o p era tin g com panies th a t th e unions sh o u ld assist th e m d u rin g th e p re se n t slu m p b y agreeing to a re d u c tio n of 17^% in w ages a n d in c o n tra c to r ’s earnings. t h i s suggestion, as th e com panies ex p lain ed , w ould still m ean th a t th e y w ould shoulder m ore th a n half th e loss, b u t it w as n ev e rth ele ss re je c te d b y th e u nions. B ro k en H ill N o rth h av e closed th e B ritish m ine a n d B lock 14 h as since been closed. I t is s ta te d t h a t th e w orks of th e E le c tro ly tic Z inc C om pany of A u stra lia are n o t affected b y th e closing dow n of these m ines, as larg e sto ck s of co n c e n tra te s are still a v a ila b le .
T o w ard s th e m id d le of J u n e th e M ount L yell M ining a n d R a ilw a y C om pany an n o u n c ed t h a t ex ten sio n s of th e con
c e n tra tin g p la n t a n d of th e e lec tro ly tic refinery, w hich w ould en ab le th e o u tp u t of copper to b e in creased to 13,000 to n s per an n u m , h a d been au th o rized . T he m ill, as reo rg an ized , w ould b e cap ab le of tre a tin g 1,000 to n s of ore p e r day . T h is to n n a g e it w as e s tim a te d w ould en a b le a pro fitab le o u tp u t of copper to be m a d e w ith ore of a low er g ra d e th a n h ith e rto . T h is a n n o u n c e m e n t w as follow ed b y a n o tic e t h a t th e c o m p an y h a d decided to m a k e a n issue of 257,839 "new shares a t p a r a n d to offer th e se to p re se n t sh a re h o ld ers in th e p ro p o rtio n of one new sh a re for ev ery five shares held.
B u r m a .— T h e B u r m a C o rp o ratio n h a s an n o u n c e d in te re s tin g d ev e lo p m e n ts on tw o lodes. T h e M ein g th a or e-body h a s b ee n c u t on N o. 2 a n d N o. 6 levels. O n th e form er a c ro ss-cu t e a s t a t 3,502 ft. s o u th ex p o sed
52§ ft. of ore a ssa y in g 15% le a d , 14-1% zinc, 3-9% c o p p e r, a n d 1 6J oz. silv e r p e r to n , w h ile on N o. 6 le v e l a cro ss-c u t w e st a t 2,756 ft. s o u th h a s ex p o se d 8 ft. tr u e w id th le a d ore a ssa y in g 23-4% le a d , 13-7% zinc, 0-1% co p p e r, a n d 18J oz. silv e r p e r to n a n d , in a d d itio n , 4 ft. tr u e w id th of co p p er ore a s sa y in g 0-2% le a d , 4-2% zinc, 6-6%
co p p e r, 2-68% n ic k e l, 0-87% c o b a lt, a n d 5-9 oz. silv e r p e r to n . T h e S h a n lo d e h a s b e e n c ro ss-c u t on N o. 9 a n d N o. 10 levels.
O n th e fo rm e r a c u t e a s t a t 689 ft. n o r th ex p o se d 1 \ ft. of ore a ssa y in g 34-7% le a d , 18-1% zinc, 0-2% co p p e r, a n d 25-9 oz. silv er p e r to n , w h ile on N o. 10 le v e l a cro ss-cu t e a s t a t 260 ft. n o r th h a s e x p o s e d 1 2 | ft.
ore a s s a y in g 3 1 '2 % lead , 14’3 % zinc, 0 T % c o p p e r, a n d ‘XI \ oz. silv er p e r to n .
M a la y a .— A c irc u la r to th e sh a re h o ld e rs of th e I p o h T in D re d g in g , L td ., w a s issu e d w ith th e a n n u a l re p o rt. T h e c irc u la r s ta te s t h a t , in v iew of th e lim ite d a re a re m a in in g to b e w o rk e d b y N o. 1 d redge, a p p ro x im a te ly 400 ac res of tin -b e a rin g g ro u n d in th e U lu L a n g a t d is tric t, n e a r A y er E ta m , h a v e b een a c q u ire d . Of th e n ew a r e a it is co n sid e re d t h a t 85 ac res a re su ffic ie n tly ric h to be w o rk e d a t th e p r e s e n t p rice of tin . I n a d d itio n a d re d g e h a s b ee n p u rc h a s e d from t h e A m p a n g (P erak ) T in D re d g in g Co., L td . (in liq u id a tio n ). T h is d re d g e is c a p a b le of tre a tin g 150,000 cu. y d . p e r m o n th .
T h e T a le rn g T in D re d g in g C o m p an y in a c irc u la r to sh a re h o ld e rs an n o u n c e s t h a t th e d re d g e h a s b e e n su ccessfu lly tr ie d o u t, b u t t h a t it h a s b e e n d e c id e d to su sp e n d a c tiv e o p e ra tio n s fo r a n in d e fin ite p erio d , th o se re sp o n sib le h o ld in g th e v ie w t h a t it w o u ld b e u n d e s ira b le to d is s ip a te th e e x h a u s tib le reso u rc e s of th e c o m p a n y a t th e p re s e n t u n ec o n o m ic p ric e level. The d red g e tria ls h a v e sh o w n t h a t 200,000 cu. y d . p e r m o n th c a n b e h a n d le d , a n a m o u n t w h ich i t is e s tim a te d w o u ld y ie ld 780 to n s of tin ox id e a n n u a lly . E x p lo r a tio n h a s b ee n c o n tin u e d a n d th e ore re se rv e s of th e c o m p a n y h a v e b e e n in c re ase d .
P a n a m a .— I n th e s ix te e n th pro g re ss re p o rt of th e P a n a m a C o rp o ra tio n f u rth e r d e ta ils a re g iv e n of w o rk on th e e x te n sio n of th e M in a B la n c a lode a t L a C uelga, 5,000 ft.
n o r th of th e m a in w o rk in g s. A t th e tu n n e l face th e g o ld c o n te n t of th e lode w as 38s.
t o th e to n o v e r 24 in . D ev e lo p m e n t h a s also b e e n c a rrie d o u t a t o th e r p o in ts n o r th a n d s o u th of th e m a in w o rk in g s. A t C erro C ab allo , 40 m iles w e st of M ina B la n c a , a tu n n e l h a s re v e a le d ore a ssa y in g 79s. o v er
48 in. O n th e s o u th e rn p o r tio n of th e R e m a n c e p ro p e rty th e m in e on P o w d e r H o u se H ill is b ein g p r e p a re d for s to p in g o p e ra tio n s. I n o rd e r to in c re ase th e r a te of d e v e lo p m e n t a n d a t th e sa m e tim e to o b ta in r e tu r n s of g o ld on a co m m ercial sc ale as so o n as possible i t h a s b e e n d ec id e d to in s ta l h y d ra u lic k in g p la n t im m e d ia te ly to w o rk t h e d ep o sits on E l M ineral in B lo ck 1.
T h is w ill b e th e th ir d p ro d u c in g p la n t n ow u n d e r c o n s tru c tio n .
S p a in .— A n in te rim r e p o r t issu ed b y th e T ig o n M ining a n d F in a n c e C o rp o ra tio n s ta te s t h a t th e e re c tio n a n d in s ta lla tio n of th e m in in g m a c h in e ry a n d e le c tric p la n t on th e s u lp h u r m in e s in S p ain b e lo n g in g to th e c o rp o ra tio n h a v e b e e n c o m p le te d . T h e m a c h in e ry in s ta lle d h a s a c a p a c ity m o re th a n sufficient to s u p p ly th e p r e s e n t t r e a t m e n t p la n t, th e first u n i t of w h ic h h a s also b e e n e re c te d . T h e c o rp o ra tio n h a s a rra n g e d to p u rc h a se tw o w ell-k n o w n s u lp h u r- p ro d u c in g p ro p e rtie s in Chile.
I t a ly .— A c irc u la r to sh a re h o ld e rs of R a y w e a v e rs, L td . s ta te s t h a t th e c o m p a n y h a s a c q u ire d a o n e-h a lf in te r e s t in a c o m p a n y
•owning a sb e sto s m in e s in n o r th e r n I ta ly ..
T h e p ro p e rtie s h a v e b e e n e x a m in e d b y M essrs. B ew ick, M oreing, a n d Co. a n d i t is e s tim a te d t h a t th e v isib le su p p lie s of ore c o n ta in 300,000 to n s of asb esto s. I t is p ro p o se d to e s ta b lish p ro d u c tio n o n a b a sis of 2,000 to n s p e r a n n u m .
F lin t s h ir e .— T h e H a lk y n D is tr ic t U n ite d M ines, L td ., a re en g a g ed in e x te n d in g th e old M ilw r T u n n e l, w h ic h s ta r t s fro m sea- le v el on th e R iv e r D ee a n d h a d b e e n d riv e n 3-37 m iles b efo re th e p r e s e n t c o m p a n y to o k th e w o rk o v er. T h e e x te n sio n to th e m id d le of J u n e h a d b ee n d riv e n 7,246 ft. T h e w o rk h a s b e e n h a m p e re d b y in ru s h e s of s a n d a n d w a te r, b u t c o n d itio n s a re im p ro v in g a n d d u rin g 12 re c e n t w eek s th e a v e ra g e a d v a n c e w as 149-4 ft., th e b e s t w eek sh o w in g a n a d v a n c e of 169 ft., w h ic h is p r o b a b ly a re c o rd for th is c o u n try . D u rin g th is w eek of 138 h o u rs 27 c u ts w ere s h o t, a v e ra g in g 6-26 ft.
each , a n d th e b e s t tim e fo r a c o m p le te cycle of o p e ra tio n s w as 4 h o u rs. T h e tu n n e l is 10 ft. w ide b y 8 ft. h ig h , w ith a w a te rw a y 4 ft. w id e b y 2 ft. 6 in . d e e p in a d d itio n , a n d is b ein g d riv e n in m a ssiv e lim e sto n e w ith a g ra d e o f 1 in 1000. C o n s u m p tio n of e x p lo siv e s is p a r tic u la rly h e a v y . T w o S 70 In g e rso ll- R a n d d rills a re u se d , w ith a S u lliv a n slu sh er for m u c k in g , a n d h a u la g e is effec ted b y m e a n s of a B .E .V . sto ra g e b a t t e r y lo c o m o tiv e .
T H E ESTIMATION OF SMALL QUANTITIES OF TIN
By J . E . C L E N N E L L , B .Sc., A .I.M .M . P A R T I . — V O L U M E T R IC M E T H O D
In t r o d u c t o r y.— T h e o rd in a r y m e th o d for th e e s tim a tio n of tin b y re d u c tio n of a s ta n n ic s a lt in h y d ro c h lo ric ac id so lu tio n b y m e a n s of iro n or n ic k el, a n d th e t i t r a t i o n of th e sta n n o u s c h lo rid e th u s fo rm e d w ith io d in e , gives s a tis fa c to ry re s u lts w ith fa irly la rg e a m o u n ts of tin . W h e n , h o w e v e r, th e q u a n t ity to b e e s tim a te d a m o u n ts to o n ly a few m illig ra m s i t becom es ex tre m e ly difficu lt to a v o id v a rio u s sources of erro r.
I n o r d e r to e s tim a te m in u te differences it is n e c e s sa ry to u se a w ea k er io d in e so lu tio n th a n t h a t co m m o n ly em p lo y ed , h en ce tra c e s of im p u r ity w h ic h h a v e a n a c tio n on iodine ca u se m o re serio u s erro rs. M oreover, w ith e x tre m e ly d ilu te so lu tio n s of s ta n n o u s c h lo rid e i t is d ifficu lt to m a in ta in th e t i n in th e s ta n n o u s c o n d itio n a fte r re d u c tio n , d u rin g th e cooling n ec e ssa ry befo re tit r a tin g w ith iod in e. O x id a tio n is lia b le to ta k e p la c e o n in tro d u c in g th e s ta rc h in d ic a to r a n d som e a t te m p t is u s u a lly m a d e to m a in ta in a n a tm o s p h e re of C 0 2 a b o v e th e liq u id before a n d d u rin g tit r a tio n , b y th e in tr o d u c tio n of a s m a ll p iece of m a rb le o r a little so d iu m b ic a rb o n a te in to th e so lu tio n im m e d ia te ly a fte r re d u c tio n . T h is is n o t a lw a y s effe c tiv e , a n d m a y b e th e m e a n s of in tro d u c in g u n d e s ira b le im p u ritie s .
Ex p e r i m e n t s o n Ti t r a t i o n o f Sm a l l Am o u n t s o f Ti n b y Io d i n e.— I n o rd e r to te s t th e deg ree of a c c u ra c y o b ta in a b le b y th e o rd in a ry m e th o d of tit r a tio n , th e follow ing so lu tio n s w ere p r e p a re d :—
S ta n n ic C h lo rid e: 0-5 grm . p u re tin d isso lv ed in 10 cc. conc. HC1 w ith a d d itio n of 0-33 g rm . K C 10S ; s o lu tio n b o ile d for som e tim e a n d d ilu te d to 500 cc. (1 cc. of th is so lu tio n = 1 m g r. S n ).
Io d in e S o lu tio n (Io d in e in K I) a p p r o x i
m a t e l y A (1 cc. so lu tio n = 0-66 m g r. Sn).
Starch em ulsion p re p a re d w ith a d d itio n of a lit tle N a O H as a p re se rv a tiv e .
M ethod.— M easu red q u a n titie s of th e t i n so lu tio n w ere acidified w ith HC1 so as to o b ta in a b o u t 1 v o lu m e of conc. HC1 in 4 v o lu m e s of so lu tio n . 4 o r 5 sm a ll clean iro n n a ils w ere in tro d u c e d a n d th e m ix tu re h e a te d to b o ilin g in a conical flask, in th e m o u th of
w h ich w as p la c e d a fu n n el c o n ta in in g a sm a ll piece of m a rb le. T h e liq u id w as th e n k e p t n e a r boilin g p o in t, for th e re q u ire d tim e n ec essary for co m p lete re d u c tio n , u su a lly 10 to 15 m in u te s. T h e flask w as th e n r a p id ly cooled u n d e r th e ta p , th e m a rb le a n d a little s ta rc h em ulsion a d d e d , a n d th e liq u id ti t r a t e d w ith o u t rem o v in g th e n ails.
T h e re s u lts a re show n in T a b le 1.
Ta b l e 1
T in Solution Conc. H C l Iodine
taken. S n Added, required. T in fo u n d
cc. mgr. cc. cc. S n mgr.
10 10 3 15-0 9-9
20 20 6 30-1 19-9
30 30 9 44-15 29-1
T e n m in u te s h e a t i n g in e a c h case.
Te s t s w i t h m o r e d i l u t e So l u t i o n s.—
T h e ab o v e re su lts a p p e a re d to be fa irly s a tis fa c to ry , ex c e p t th a t th e re w as a te n d e n c y for th e b lu e s ta rc h colour to fad e r a p id ly a fte r th e titr a tio n , so t h a t in som e cases th e e x a c t e n d -p o in t w as u n c e rta in . I t w as th o u g h t th a t th is m ig h t b e due to som e carb o n c o m p o u n d in tro d u c e d b y th e iro n n ails. P u re iro n w ire, as u se d for sta n d a rd iz in g so lu tio n s, w as th e re fo re em p lo y ed in th e follow ing te sts.
Som e ex p e rim e n ts w ere m a d e in w hich H 2S 0 4 w as s u b s titu te d for HCl, b u t th is show ed no p e rc e p tib le a d v a n ta g e . T he so lu tio n s u se d w ere :—
S ta n n ic Chloride. T h e p rev io u s so lu tio n d ilu te d so th a t 1 cc. = 0-1 m g r. Sn.
Io d in e. 1 cc. = 0-637 m gr. Sn.
A b o u t 1 g rm . of iro n w ire w as u se d in each te s t. H e a tin g w as co n tin u e d for 10 to 15 m in u te s. T h e en d -p o in t w as p e rfe c tly sh a rp . T h e re s u lts o b ta in e d are s h o w n in
T a b le 2.
Ta b l e 2
T in Solution Conc. Iodine
taken. S n . H C l. required. S n fo u n d ,
cc mgr. cc. cc. mgr.
10 1 6 1-55 1-06
20 2 6 3-1 1-97
30 3 10 4-65 2-96
40 4 13 6-3 4-01
50 5 17 7-95 5-06
A tte m p ts w ere m a d e to tit r a t e s till sm a lle r q u a n titie s of tin (0-1 to 1 m gr.) b y th is m e th o d , b u t i t w as n o t fo u n d p ra c tic a b le , 9
