The Mining Magazine
M aniiging Director and E d ito r : W . F . W h i t e . A ssista n ts: S t. J. R . C. S h e p h e r d , A .R .S .M ..D .IX ., F .G .S .,
F . Hi g h a m, A . R . S . M . , M . S c . , F . G . S . ’’’
Pu 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 Mi n i n g Pu b l i c a t i o n sC ' ^ M i t e d - a t S a l i s b u r y Ho u s e, Lo n d o n, E . C . 2 .
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I Chicago : 360, N . M ichigan Blvd. I U.S.A., $3 j
L O N D O N , JA N U A R Y ,
1932. V . % ^ NEP|
C O N T E N T S
_ PAGE
Ed i t o r i a l
N o te s . . .
New Y ear H o n o u rs ; In s titu te of M etals’ A m erican M eeting P o stp o n ed ; A w ard of Jam e s D ouglas M edal of th e A m erican I n s titu te ; New S ecretary- T re a su re r of C anadian In s titu te ; New Ore-Dressing L a b o rato ry a t B irm in g h am U niversity Opened ; I n s titu tio n ’s New P resid en t.
Gold and S ilv e r... 2
P roceedings a t th e D ecem ber m eetin g of th e In stitu tio n are discussed. M etals in 193 1... 4
An ex am in atio n of b ase-m etal conditions a t th e end of th e p a st y ear. F a ra d a y and M etallu rg y ... 5
A new b o o k of S ir R o b ert H adfield’s is reviewed. Re v i e w o f Mi n i n g... 6
Ar t i c l e s U g a n d a ... E . J . W ayland The D irecto r of th e Geological S u rv ey of U ganda gives an ac c o u n t of th e geology of th e P ro te c to ra te in relatio n to m ineral deposits a n d w a te r supply. A lluvial M ining w ith M echanical E x c a v a to rs ... W . E. Sinclair An outline of a schem e fo r w orking ce rtain ty p es of alluvial d ep o sits b y m eans of a co m b in atio n of d ra g line e x c a v a to r an d drag-scraper. The B eatrice Mine, Selibin, F.M.S. E. S. W illbourn (Concluded from the December issue, frage341) K a ta n g a Tin P ro p erties. .R . W . Scott The au th o r gives a descrip tio n of w ork on certain alluvial deposits of w hich relativ ely little is known. B o o k Re v i e w s ^ G u te n b e r g 's " H a n d b u c h d e r G e o p h y s ik G u te n D e rg ^ H o g » . » » ; ; T T “ . d “ . 5 'T T S .. ^ g e w ä h l t e M e th o d e n fü r S c h ie d s- A u sg a n d P r o b e n a h m e v o n a n a ly s e n ... c w D a n n a tt . E rz e n _ • • p r a c t j,c a i H a n d b o o k o n W a t e r D ixey s ... H r. M u rra y Stuart Supply ... T 0 t h e E d i t o r Le t t e r The S c i e n t i f i c F u ndam entals of r r a v i t y C oncentration 1 • R. T. Hancock News Le t t e r s 15 20 24 27 28 29 30 31 Jo h a n n e sb u rg. ... 31
W e s t R a n d ; E luvial Gold D iscovery ; A ncient Tin ’ Discovered ; H igher E x tractio n a t G lynn’s ; PAGE B r i s b a n e ... 3 2 M ount Isa’s Position ; M ount Isa P roduction and O p e ratio n s; Cloncurry M inerals ; Mining Concessions ; Coal T rade ; Gold Prospecting and P roduction. V a n c o u v e r ... 3 4 P o rtla n d Canal ; A tlin ; U sk ; Cariboo ; B ridge R iv er ; B o u n d a ry ; Nelson : A nnual W estern M eeting of C anadian In stitu te. T o r o n t o ... 3 6 Gold Production of O n ta r io ; Porcupine ; K irkland L ake ; S ud b u ry ; R ouyn ; P atricia ; M anitoba. Pe r s o n a l... 3 9 Tr a d e Pa r a g r a p h s... 3 9 M orse F lexible C o u p lin g ... 39
K ru p p R a k e C la s s if ie r ... 40
W ilfley-W illiam s V ib ra tin g S c r e e n ... 41
D o u b le -U n it G en ter-T y p e F i l te r ... 41
B u c y ru s-E rie B alanced H o ist for S h o v els. . 42
Ja m es S c r e e n s ... 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 Mi n i n g Di g e s t M ine V en tila tio n w ith P ropeller F an s F. A . Steart and R . Henderson 49 A N ew H o ist for th e L ak e Shore Mine G. A . Young 53 L ead-Z inc D ep o sits on th e Gold C oast Dr. C. M . Tattam 55 A N ew G uinea Gold M i n e .. /. W. M orley 58 H a u lag e a t N o ra n d a ...B . Robinson 59 G round B reak in g a t a C an ad ian M ine A . R . Lawrence 61 Gold M illing a t th e A rg o n au t Mine S. E . Woodworth 62 Sh o r t No t i c e s... 6 2 Re c e n t Pa t e n t s Pu b l i s h e d... 6 3 Ne w Bo o k s, Pa m p h l e t s, e t c. Co m p a n y Re p o r t s... Far Sherw °°d S ta r r ’s O re-B odv ; X -R ays Used in Mines. 63 . . . . 63
A pex (Trinidad) Oilfields ; H ongkong T in ; K am unting T in ; M essina (Transvaal) D ev elo p m e n t; P a tta n i T i n ; Sulphide C orporation. N e w C o m p a n i e s R e g i s t e r e d ... 64
D i v i d e n d s D e c l a r e d ... 64
EDITORIAL
rT ''H E New Y ear H onours L ist contains b u t X tw o nam es of in tere st to our readers, D r. H arold Moore, D irector of M etallurgical R esearch, W ar Office, and Mr. G. K. Menzies, S ecretary of th e R oyal Society of A rts, each receiving th e C.B.E.
J
N view of th e prevailing d istu rb ed economic a n d financial conditions, th e Council of th e In stitu te of M etals has decided to postpone th e 1932 m eeting, w hich w as to hav e been held in th e U n ited S tates and C anada in th e A utum n.D
R. C. H . M ATHEW SON, of Yale U niversity, has been nom inated Jam es Douglas m edallist of th e A m erican In stitu te of Mining and M etallurgical Engineers for 1932. T h e aw ard is in recognition of “ his scientific con trib u tio n s to th e a rt of w orking and annealing non-ferrous m etals.”T
H E new Secretary-T reasurer of th e C anadian In s titu te of Mining and M etallurgy is Mr. E. J . Carlyle, who is well- know n to m an y on th is side. Mr. Carlyle has h a d extensive professional experience, w hich should prove invaluable a t a tim e w hen depression is seriously affecting mining affairs.A
D E S C R IP T IO N of th e new ore-dressing lab o rato ry a t B irm ingham U niversity appeared in th e last issue of th e M a g a z i n e .The new building was opened by Sir R o b ert H orne on Decem ber 16, those present subsequently having th e o p p o rtu n ity of exam ining th e adm irable facilities available a t th is U niversity for th e training of stu d en ts, p articu larly in th e m ining of coal. A fter a cerem onial luncheon, Sir R o b ert H orne and Mr. E v an W illiam s received h onorary degrees a t th e h ands of th e Vice-Chancellor, Sir Charles G ran t R obertson.
T
H E president-elect of th e In s titu tio n of Mining a n d M etallurgy for 1932-33 is Dr. Sydney W. Sm ith. Dr. Sm ith, who g ra d u ated from th e R oyal School of Mines in m etallurgy in 1899, is a D.Sc. of London U niversity, a M ember of th e In s titu te ofMetals, a Fellow, of th e In stitu te of Chem istry, a n d a Fellow of th e Chemical Society. He has been a M em ber of th e In stitu tio n since 1908 an d a V ice-President since 1929 an d in 1926 was aw arded th e Gold Medal of th e Consolidated Gold Fields of South Africa, L td . On th e occasion of th e E m pire Mining a n d M etallurgical Congress in S outh Africa in 1930— in connexion w ith w hich D r. Sm ith co n trib u ted a series of articles to T h e M i n i n g M a g a z i n e— th e new president was m ade an H onorary D.Sc. of th e U niversity of th e W itw atersrand. Dr. Sm ith com m enced professional w ork in 1899 as assista n t to th e late Sir W illiam R oberts-A usten in connexion w ith th e w ork of th e Alloys R esearch Com m ittee of th e In s titu tio n of M echanical Engineers. H e was appointed T em porary A ssistant Assayer a t th e R oyal M int in 1900 a n d passed th ro u g h th e position of A ssistant A ssayer to th a t of Chief Assayer, which he has held since 1926.
G old and S ilv er
The D ecem ber m eeting of th e In stitu tio n is not usually one of th e b est a tten d ed , m em bers generally having so m an y season
able calls on th e ir tim e, so th a t th e large num ber present a t last m o n th ’s gathering evidenced th e keen interest aroused b y th e p ap er to be discussed— “ Gold an d Silver as Money M etal,” by Mr. T. A. R ickard.
Several distinguished guests were also present an d th e in terest displayed serves to em phasize th e a n x iety of all to help in th e correction of those failings of present-day economics, w hich are generally regarded as th e m ajor cause of th e prevailing depression.
The subject under discussion dealt n o t only w ith m oney, b u t w ith gold an d silver, tw o m etals of such im portance to all m ining engineers th a t even those who professed to know nothing of m o n etary th eo ry could a t least feel th a t th e m a tte r h a d an in tim a te bearing on th eir own im m ediate problem , th a t of growing unem ploym ent.
I t m ay be said a t once th a t Mr. R ic k a rd ’s p ap er is a plea for th e re-establishm ent of a bim etallic m o n etary sta n d a rd b y th e resto ratio n of silver to a place in p artn ersh ip w ith gold. He states th a t th e adoption of th e gold sta n d a rd was generally accepted in th e belief th a t sta b ility of in te rn a tio n a l 2
price levels w ould ensue and th a t this belief has tu rn e d out to be false. P rior to th e adoption of th e m onom etallic basis for in tern atio n al exchange purposes bim etallism is said to have functioned satisfactorily, b u t th e discoveries of silver in th e western U nited S tates some six ty years ago caused a scare which drove m ost of th e im portant powers on to th e gold stan d ard , silver being retain ed b y some of these for use in sub
sidiary coinage only. Mr. R ickard regards as baseless th e panic which caused these h a s ty abandonm ents of bim etallic currency an d states th a t the dem onetization of silver during th is period can find no justification in th e statistics of mining. As is usual in all surveys of m etallic m oney stan d ard s and th e ir bearing on present conditions in world trade, th e au th o r stresses th e im portance of relations w ith those eastern nations whose affairs are still in tim ately associated w ith silver—chiefly China, which is still on a silver stan d ard , and India, which, while on a gold-exchange stan d ard , has so much hoarded w ealth in th e form of silver m etal.
Mr. R ickard is not alone in considering th a t th e gold sta n d a rd has tended to demoralize eastern m arkets for w estern products and he urges th e adoption of speedy measures to counteract such an impossible position, proposing th e setting up of a bim etallic sta n d ard based on a ratio of gold to silver a t 1 : 15 as being th e one step m ost likely to lead to im provem ent. Finally, th e paper lays stress on th e fact th a t bim etallism is nothing th a t is new and em phasizes th e view th a t its readoption would only be a retu rn to a well-tried m onetary system.
In introducing Mr. R ickard’s paper the president— Mr. Pellew -H arvey—showed the im portance of silver prices to base-m etal producers an d held this to be a justification for th e exam ination by all m ining engineers of w hat m ight otherwise be considered as purely a question for economists. He, too, laid stress on relations w ith eastern peoples, agreeing w hole-heartedly w ith th e a u th o r’s view th a t th e deterioration of eastern trad e m ight ju stly be considered as closely related w ith th e fall in silver prices. A fter con
sidering various schemes which have been advanced for th e rehabilitation of silver m etal, Mr. Pellew -H arvey rem inded those present th a t th e In stitu tio n in seeking to v entilate th e m a tte r should approach it from a natio n al and not a selfish standpoint.
The paper was th e n briefly b u t adequately introduced by th e au th o r and throw n open
to discussion, th e first speaker being Mr. J. A.
Agnew, who im m ediately threw his weight on th e side of the bim etallists, laying equal em phasis w ith th e au th o r on th e likely effect of such a step on th e restoration of eastern trade. Mr. Agnew was followed by Sir H enry Strakosch, who, by m eans of carefully prepared statistics, urged th a t it was too early to say th a t gold had failed th e world, and d em onstrated th a t bim etallism could not in th e least have prevented th e flow of bullion to th e great creditor nations, France and th e U nited States, and, turning to statistics once again, held th a t conditions w ithin China and India were really not so b a d after all, although their external trad e was w ithout doubt lim ited by silver prices. Mr. F. H. H am ilton, in his contribution to th e discussion, pointed out th e un fo rtu n ate effect of th e stabilization of th e rupee a t Is. 6d. an d Col. F. L. H arden, who followed and who was very much a bim etallist, in his enthusiasm clearly had m uch of th e m eeting w ith him. O ther speakers included Mr. Gilman Brown and Mr. Cull, th e la tte r taking th e view th a t synm etallism h ad yet to be proved un workable.
The result of th e evening’s discussion leaves m atters p re tty m uch where th ey were.
The subject rem ains an extrem ely debateable one, it not being difficult to produce argum ents for and against such a step as is advocated in the paper. The w orld’s pro
duction of gold can hard ly hope to keep pace w ith th e growing needs of commerce, so th a t some step m ust be tak en sooner or later in an endeavour to restore price levels to an equitable basis. The adoption of bim etallism would, a t least, be som ething concrete, it is app aren tly easy, and, as the au th o r has said, it has been tried. I t is doubtful, however, w hether international agreem ent on the adoption of a bim etal sta n d ard would be easy of achievem ent—
in fact, in view of th e uncontrollability of silver supplies, it m ight alm ost be called impossible, for a dual stan d ard calls for perfect price substitution of one m etal sta n d a rd for th e other. Here appears to be th e crux of th e problem : Could an in ter
national agreem ent on th e price ratio of gold to silver counteract the n a tu ra l price ratio created b y production costs ? Bi
m etallists an d m onom etallists will doubtless answer this question to th e ir own satis
faction ; we fear we cannot answ er it for them .
4 T H E M IN IN G MAGAZINE M etals in 1931
T he course of prices of th e leading non- ferrous m etals during 1931 proved a severe disappointm ent, not only to th e producers, b u t to th e various big syndicates a n d groups desirous of controlling m arkets. Prices generally fell to th e lowest level for m any years an d copper an d spelter broke all records. The un satisfacto ry results a tten d in g th e efforts of th e Copper Producers to capture w orld tra d e have been approached only by th e confusion created by th e speculative groups engaged for a very long period in m an ip u latin g tin, b u t in th e la tte r case th e G overnm ents concerned eventually cam e to th e rescue and, b y enforcing drastic cuts in production an d encouraging th e speculative operations of th e In te rn a tio n a l Tin Pool, the decline in prices was checked. In th e middle of last year tin changed han d s in th e neigh
bourhood of £100 and the subsequent advance to over £140 appears im pressive u n til it is rem em bered th a t th e im provem ent is largely due to th e fall in sterling. Lead, of course, is closely controlled by th e organization of producers, as, too, is spelter. B roadly speak
ing, all th e m ain non-ferrous m etals are to d a y controlled, more or less, an d should therefore be in a technical position to respond to any favourable developm ent in trad e, b u t th e world-wide chaos involved by th e R ep ara
tions futilities has paralysed th e channels provided for th e in te rn atio n al exchange of com m odities, which m akes th e future som e
w hat obscure.
T aking th e m etals separately, th e copper in d u stry w ent from b a d to worse last year.
In M icawber-like fashion th e producers carried on, tru stin g th a t som ething would tu rn up to rectify a situ atio n th a t was stead ily becom ing alm ost hopeless. W hen th e year opened th e refined copper stocks in A m erica am ounted to some 367,000 short tons, b u t by th e end of th e year th e estim ate h ad soared to 550,000 tons. The official m o n th ly figures of A m erican o u tp u t, deliveries, an d stocks were suspended in th e A utum n and negotiations which took place from tim e to tim e failed to result in a n y agreem ent which m ight have helped to rem edy th e situ atio n . W orld o u tp u t tren d ed g radually dow nw ards under economic pressure, b u t there was actually a slight increase in Am erica in th e m iddle of the year, although late r th e producers there began to cut operations quite substantially.
A t th e eleventh hour, w hen Copper E x p o rters
looked like breaking-up, some 90 per cent, of th e w orld’s producers agreed to cut down th e ir operations during 1932 to 40 per cent, of th eir capacity, estim ated a t 2,250,000 tons.
D rastic as th is cu rtailm en t is, it is som ew hat doubtful w hether it will be sufficient to reduce stocks a t th e desired rate.
D uring 1931 tin h isto ry is v ery largely a sto ry of th e progress of th e q u o ta scheme of th e G overnm ents concerned. A fter m onths of negotiation an d th e failure of th e schemes for v o lu n ta ry cu rtailm en t of o u tp u t, th e com pulsory plan was enforced from M arch 1 b y legislation in M alaya, Nigeria, Bolivia, a n d th e D u tch E a s t Indies, whose aggregate a n n u al o u tp u t was lim ited to 125,845 tons.
From Ju n e 1 th is figure was reduced fu rth er to 106,096 tons, w hilst from Septem ber 1, w ith th e inclusion of Siam in th e scheme, it rose to 116,096 tons, subsequently falling to 101,096 tons, operative from J a n u a ry 1, 1932. T he enforcem ent of th is scheme, p articu larly in th e early stages, was accom panied b y m uch confusion and, w ith con
sum ption declining steadily, th e visible supply—including th e carry-over in th e E a s t—rose over 13,000 to n s during th e year. D em and fell so severely th a t w orld production has now been reduced some 40 per cent, from th e 1929 level. In A ugust an In te rn a tio n a l Pool was form ed to acquire surplus stocks of tin up to a m axim um of about 25,000 tons, of which a t th e m om ent it holds some 19,000 tons, b u t none of th is m ay be liq u id ated u n til th e price averages
£165 th ro u g h o u t one calendar m onth. W ith th e G overnm ents in th e q u o ta scheme pledged to m ain tain th e restrictions u n til August, 1934, if necessary, in order to facilitate the liquidation of th e P ool’s stocks, an d w ith p roduction cu rtailed drastically, tin values should im prove, b u t th e in te rn a tio n a l situ a tion is so difficult th a t even now th e im m ediate outlook is uncertain.
Viewed in com parison w ith th e other m ajor non-ferrous m etals, lead suffered less from th e depression last year, b u t 1931 was a n y th in g b u t a good period for producers.
The slum p in silver affected th e lead in d u stry adversely an d w ith consum ption well below recent levels, especially on th e C ontinent an d in America, over-production was seen, accom panied by falling prices.
To rectify th is th e L ead P ro d u cers’ Associa
tion in au g u rated a 15 per cent, cu t in o u tp u t on May 1, increasing th e cu rtailm en t to 20 per cent, from Ju ly 1. W ith a spell of buying here following th e suspension of the
gold sta n d a rd th e m ark et preserved a p re tty stead y tone in th e closing m onths of th e y ear an d w ith a strong control of supplies and stocks is in a position to ta k e advantage of any im provem ent in general conditions.
Of all th e groups of producers still endeavouring to control non-ferrous m etals th e new Zinc Cartel, which fructified during 1931, has probably been th e m ost successful.
The continued economic crisis gave spelter m akers tw o altern ativ es— either to let com petition ta k e its u n restricted course and force th e dearer-cost producers out of existence or to combine am ongst them selves an d regulate o u tp u t. T he la tte r course was a d o p ted in Ju ly , w hen the Cartel was formed, an d in A ugust o u tp u t was reduced to 55 per cent, of th e 1927-1930 basis. The C artel’s stocks began a t once to fall, receding from 228,000 tons in Ju n e to 186,000 to n s in December. Consum ption has been u n satis
factory, b u t producers are g ettin g th e situ a tion under control, although th ere exist fu rth er large stocks in Am erica not under direct C artel control.
F arad ay and M etallu rgy
The centenary celebrations held in London last year to m ark w hat was undoubtedly the m ost im p o rtan t discovery of Michael F arad ay
—th a t of electro-m agnetic induction— served to bring light on m any of his activities which were to m ost people alm ost unknow n.
At the B ritish Association m eeting Sir R obert H adfield surveyed F a ra d a y ’s m etal
lurgical work in a paper which was essentially a sum m ary of w ork presented earlier before th e R oyal Society,1 a notice of which appeared in th e M a g a z i n e for October last.
This aspect of F a ra d a y ’s life has now been b rought home to a w ider public in still g reater detail by Sir R o b ert’s new book,2 which contains th e results of work on additional m aterial and goes m uch farther, tracing th e influence of those whose dis
coveries aided F ara d a y or whose p a rt was th a t of active assistants.
As has been indicated, th e scope of this illum inating book is very wide, containing all th e elem ents of carefully com pleted biographical research, in addition to a thorough survey, by m odern chemical m eans, of th e m etallurgical work itself. A fter tracing F a ra d a y ’s rise to fame, Sir R obert
1 P h il. Trans., A, vol. ccxxx, S ep tem b e r, 1931.
2 “ F a ra d a y a n d H is M etallurgical R e se arc h es.”
B y Sir R o b e rt H adfield, B a rt. P rice 21s. L ondon : C h ap m an a n d H all.
assists th e reader to gain some idea of th e conditions under which th e great experi
m enter worked, showing som ething of the influences which guided his m etallurgical studies. This section of th e book, besides presenting an adm irable sum m ary of tim es and people, is rendered m uch more valuable by a collection of p o rtraits of th e persons concerned, w ith th e exception of th a t of Stodart, whose assistance in p ractical steel work was of such help to F arad ay . Passing to th e events of th e six years, 1819-1824, which were devoted to this work, it is shown th a t th e investigations can be conveniently grouped under five headings : F irst, th e exam ination of wootz steel, which formed th e subject of a paper before th e R oyal In stitu tio n in 1819 ; secondly, a series of experim ents on alloy steels, described in his 1820 paper to th e same body ; thirdly, th e events leading to th e R oyal Society paper of 1822, “ On th e Alloys of Steel ” ; fourthly, the large-scale experim ents at Sanderson’s, Sheffield, and, finally, th e period of research covering “ The Magnetic R elation and Character of th e M etals.” The au th o r then goes on to show th a t F a ra d a y ’s work on steel and alloys m ay ju stly be regarded as th e beginning of system atic w ork on alloy steels, even if it was n o t to lead im m ediately to a period of p ractical utilization of his results. The n ex t p a rt of th e book covers a m odern investigation of F a ra d a y ’s speci
m ens and is a record of detailed, thoroughly- scientific research work. Finally, Sir R obert has w ritten an appreciation of F a ra d a y ’s work before suitably concluding w ith an o u t
line of th e later developm ent of alloy steels.
To understan d ju st w hat F a ra d a y h ad accom plished it is necessary to tu rn once again to Sir R o b e rt’s “ A ppreciation.”
D uring th e few years he was able to devote to th is branch of his researches F ara d a y carried out system atic w ork on th e alloys of steel w ith platinum , silver, rhodium , and nickel and he was th e first to a tte m p t the m anufacture of a stainless steel by alloying iron and other m etals. I t is tru e th a t the work was of little industrial use a t th e time, which explains m uch of th e unfavourable com m ent which has been m ade upon it, b u t it is rem arkable th a t the research should have anticip ated in so m any w ays the investigations of later workers. W ho knows, h ad F ara d a y been in th e position to tr y m anganese in his work, w hether he m ight not have forestalled Sir R o b e rt’s own im p o rtan t invention !
REVIEW OF MINING
In tro d u ctio n .—T he old year has passed, to th e accom panim ent of a general sigh of relief. As it is felt in m any q u a rte rs th a t things m ust have now touched b o ttom , hopes are e n tertain ed of a t an y ra te some im prove
m en t d u rin g 1932.
T ra n sv a a l.—T he o u tp u t of gold on th e R an d for D ecem ber was 877,178 oz. and in outside districts 46,175 oz., m aking a to tal of 923,353 oz., as com pared w ith 900,510 oz.
in Novem ber. L ast y e a r’s to ta l of 10,874,145 oz. constitutes a fresh record, being 154,385 oz. ahead of th e figures for 1930. T he num ber of natives em ployed on th e gold m ines a t th e end of th e m o n th to talled 211,552 as com pared w ith 209,270 a t th e end of N ovem ber.
T he accom panying tab le gives th e dividends declared b y th e R an d gold m ining com panies on account of th e p ast h alf-year. F o r th e purpose of com parison th e figures for th e preceding th ree half- years are given an d from th ese it will be seen th a t G eduld and Sub Nigel are th e only com panies to show an increase, although Rose Deep, E ast R and, and R andfontein reappear in th e list. T he figures for th e p a st half-year are, of course, in South African c u rre n c y :
1st 2nd 1st 2nd
half, half, half, half,
1<J30. 1930. 1931. 1931.
s. d. s. d. s. d. s. d.
B rak p a n ... 4 3 4 6 4 0 4 0
C onsolidated M ain R eef. . 0 0 1 3 1 3 1 3
Crown ... 3 3 3 6 3 6 3 0
D u rb an R o o d ep o o rt D eep 0 3 0 6 0 9 0 9
E a st R a n d ... — — 0 6
G eduld ... 3 3 3 3 3 3 3 0
G eldenhuis D eep ... 0 9 1 0 1 0 1 0
G o v ern m en t A r e a s ... 2 3 2 3 2 3 2 3 L a n g laag te E s ta te ... 2 0 2 0 2 0 2 0
M odderfontein B ... 2 0 2 0 1 6 1 6
M odderfontein D e e p . . . . 3 3 3 3 3 0 3 0
M odderfontein E a s t . . . . 2 0 2 0 2 0 2 0
New M odderfontein . . . . 0 9 6 6 6 0 5 0
New S tate A reas ... 1 6 2 0 2 0 2 0
N ourse M ines ... 0 (i 0 9 0 9 0 9
R an d fo n tein ... — — 0 (i
R obinson D eep (A Is.) . 1 0 1 6 1 6 1 6
Robinson D eep ( B j ... 74 44 0 ti
Rose D e e p ... I) <> 0 0 •— 0 6 S p rin g s M ines... 3 6 4 0 3 9 4 0 S u b N i g e l ... 2 0 3 0 3 0 3 0 V an R y n D e e p ... 3 0 3 0 2 6 2 0 W est S p r i n g s ... 1 0 1 0 0 9 0 9 W itw a te rs ra n d Gold . . . 1 0 1 0 0 6 0 6
S hareholders of th e Jo h an n esb u rg Con
solidated In v e stm e n t Com pany have been inform ed th a t, although th e profits earned for th e h alf-year to D ecem ber 31 last ju stify
6
a distrib u tio n , it has been decided, in view of th e prevailing financial conditions, n o t to declare an in terim dividend.
For th e purpose of providing ad d itio n al funds to cover ex p en d itu re on c a p ita l account, th e b o ard of E a st G eduld Mines has decided to issue a fu rth e r 60,000 shares.
T his new issue has been m ade u n d er th e te rm s of th e existing agreem ent w ith th e Union C orporation, w hereby th a t com pany holds a p referen tial rig h t to subscribe a t par.
T he cap ital of E a st Geduld has, consequently, been increased to £1,560,000.
I t is re p o rte d from S o u th A frica th a t negotiations are proceeding for th e acquisi
tion of th e W itp o o rt Gold A reas b y B rak p an Mines. I t will be recalled th a t developm ent operations a t th e W itp o o rt m ine were suspended in N ovem ber last, owing to lack of funds.
C ontrol of New A lbion T ran sv aal Gold Mines has been acquired by Oceana D evelop
m ent, w hich has purchased appro x im ately 51% of th e New Albion capital. I t is sta te d th a t th e purchase consideration h as been discharged w ith o u t m aterially affecting th e co m p an y ’s liquid resources.
Elsew here in th is issue will be found th e registration of a new com pany, w hich has ta k en over H .E . P ro p rie ta ry (New). This step form s p a rt of a scheme for reco n stru c
tion w hich was unanim ously appro v ed a t an ex tra o rd in a ry m eeting h eld last m o n th .
T he accounts of P o tg ie te rsru st P latin u m s for th e 11 m o n th s to A ugust 31 last show th a t th e loss carried forw ard has been increased b y £15,406 to £76,232. D uring th e period u n d er review w ork was concen
tra te d on th e K lipfontein an d K roondal portions of th e R usten b erg section, while 19,951 oz. of p latin u m group m etals an d gold was produced. As was announced in th e
M a g a z i n e for A ugust last, th e m ines of P o tg ietersru st P latin u m s were ta k e n over b y a new com pany, R u sten b e rg P latin u m Mines, on Septem ber 1, 1931, th e form er com pany receiving 262,491 fir.st preference shares of £1 each in th e new com pany.
The accounts of A frican A sbestos T ru st for th e y ear to Ju n e 30 la st show th a t th e value of asbestos sold, to g eth er w ith sun d ry revenue, to talled £2,036, against £5,423 th e
previous year, and expenses am ounted to
£1,550. I t is sta te d th a t th e board has found it impossible to raise th e fu rth er capital necessary to reopen th e mine and to install th e m ain plant.
D ia m o n d s.—T he accounts of De Beers Consolidated Mines, L td ., for th e year ended Ju n e 30 last show th e stocks of blue ground on th e floors a t th e end of th e year to be 2,141,952 loads, of which 48,396 cam e from th e De Beers m ine, 344,332 from the W esselton mine, 822,779 from the B ultfontein mine, and 926,445 from th e D utoitspan mine.
T he diam ond account for th e year am ounted to £679,553 and income from other sources to £750,244, giving, w ith th e sum brought in, a to ta l of £2,831,516. Expenses am ounted to £1,296,053, leaving a balance of £1,535,463, of which £400,000 was paid as preference dividends, th e sum of £1,135,463 being carried forward.
S ou th ern R h od esia.—The o u tp u t of gold from Southern R hodesia during Novem ber was 44,516 oz., as com pared w ith 44,260 oz.
for th e previous m onth and 44,351 oz.
in N ovem ber, 1931. O ther o u tp u ts for N ovem ber were : Silver, 7,858 oz. ; coal, 51,644 t o n s ; chrom e ore, 10,612 t o n s ; asbestos, 553 tons ; mica, 9 tons.
A t an ex trao rd in ary m eeting held last m onth shareholders of Mapeke Asbestos Mines agreed to th e v o luntary winding up of th e com pany, th e assets of which are to be sold to a new com pany w ith a similar name.
Advice from South Africa is to th e effect th a t th e Globe and Phoenix Com pany has obtained leave to appeal against th e order recently m ade in th e H igh Court giving the rig h t of inspection to th e Rhodesian C orporation.
N orth ern R hodesia.—The report of M ufulira Copper Mines for th e three m onths ended Septem ber 30 last shows developm ent work a t th e mine to have been m aking steady progress, while construction w ork has also proceeded rapidly. I t is anticipated th a t the plan t will be com pleted and ready to go into operation some tim e this m onth.
D uring th e year ended Ju n e 30 last geological w ork was continued by Rhodesia Minerals Concession, L td., b u t none of the prospects on which this was done proved of any value. The ex ten t and character of th e area, however, are sta te d to be so prom ising th a t th e w ork is to be continued.
G old C oast.— Shareholders of A shanti Goldfields Corporation, L td., have been
inform ed th a t a final dividend of 40% has been recom m ended for th e year ended Septem ber 30 last, m aking a to ta l of 90%
for the year. In addition, it is once again proposed to capitalize £125,000 of th e reserve, distributing the 625,000 shares th u s created as fully paid bonus shares to th e shareholders in the proportion of one share for every three held.
T he rep o rt of B ibiani (1927) shows th a t expenditure on sh aft sinking, etc., for th e year to Ju n e 30 last am ounted to £30,851, while £2,473 was spent on p lan t and m achinery. T he rep o rt of th e consulting engineer, Mr. J. S. W atkins, shows th a t the sta te of affairs a t th e mine is held to be promising and he recom m ends n o t only the continuance of prospecting and developm ent work, b u t th e erection of a tre a tm e n t p lan t to deal w ith 100 tons per day. T he com pany hopes to carry out these recom m endations and is considering th e provision of new capital for the purpose.
D uring th e year ended Septem ber 30 last A riston Gold Mines (1929) m ade a profit of
£502, th e deb it balance a t th e end of 1930 having been w ritten off in accordance w ith th e term s of the reorganization of capital recorded in th e M a g a z i n e in Jan u ary , 1931.
Ore m ined during th e period under review am ounted to 52,681 tons, 51,626 tons, of an average value of 10-74 dw t., being milled for a recovery of 8-66 dw t. per ton. Ore reserves a t th e end of th e year were estim ated to be 161,076 tons, averaging 11-68 dw t. in value.
The mine is now under new m anagem ent, which has abandoned shrinkage stoping as a costly failure and in stitu ted a filling m ethod.
I t was visited recently by Mr. C. B.
Brodigan, who, in anticipation of his report, states th a t he can see no reason why th e mine should n o t be working on a profit-earning basis in th e n ear future.
The rep o rt of Morkwa, L td., for th e year to Ju n e 30 last shows th a t general conditions have precluded th e com pany from m aking any fresh developm ents, although certificates of validity of title to all its diam ondiferous properties have now been obtained from the Suprem e Court of th e Gold Coast Colony.
A u stralia.—T he report of th e W iluna Gold Corporation for th e year ended March 31 last shows th a t w ork a t th e W iluna Gold Mines during this period consisted m ainly in com pleting th e installation and erection of p lant and in preparation for th e stoping of ore, tre a tm e n t commencing in March.
B y th e end of O ctober 165,709 tons of ore
8 T H E M IN IN G MAGAZINE h ad been tre a te d , bullion w orth £271,165
being recovered, w orking costs over th e sam e period am ounting to £167,129.
A lthough difficulties were experienced w ith th e pow er p la n t a t first, all th e equipm ent is now said to be w orking satisfactorily. Ore available for stoping a t th e end of th e year w as estim a ted to be 540,000 tons, assaying 33s. 6d. p er ton, w ith, in addition, 125,000 tons of probable ore below th e 450 ft. level.
W hile recoveries in th e cyanide p la n t have been satisfactory, certain alteratio n s in th e flotation p la n t have been suggested b y Mr. T. Owen, who accom panied Mr. C. O.
L indberg in his exam ination of th e p ro p erty , and it is expected th a t these will considerably im prove recovery.
B u rm a .—D uring th e y ear 1930 th e opera
tions of Mawchi Mines, L td ., showed a loss of £45,219, owing to th e low prices prevailing for m etals. B y m eans of a reorganization of capital, announced in th e M a g a z i n e for Ju ly last, th is loss has been w ritte n off. D uring th e year u n d er review a lteratio n s and additions to th e mill gave considerably im proved results, milling being re sta rte d in F eb ru ary , 1930, and 42,741 tons tre a te d by th e end of th e year. T he concentrates recovered am ounted to 2,018 tons, while 169 tons was purchased from n ativ e workers.
A t D ecem ber 31, 1930, th e proved ore reserves were e stim ated to be 123,047 tons, of an average value of 4-35% com bined tin and w olfram . T he cessation of developm ent early in 1930 caused th is figure to fall to 77,855 to n s a t th e end of Septem ber last and developm ent m ay soon be resum ed.
M alaya.—T he re p o rt of K ay Yew (K inta Valley) Tin Mines for th e year 1930 shows th a t 274 tons of tin concentrates w as pro duced, w hich realized £87 2s. Id . per ton, operations resulting in a loss of £5,709. In th e c u rren t year m any drastic economies have been m ade in an endeavour to carry on and 100 tons of tin concentrates was produced b y Septem ber 30, w hen th e m ine was tem p o rarily closed down, production re
sta rtin g on D ecem ber 1 last. Proposals for th e reorganization of th e com pany’s c ap ital are u n d er consideration.
A t a m eeting of T eja M alaya T in D redging last m o n th a resolution for w inding up the com pany an d appointing a receiver was approved.
C hina.—T he accounts of th e Chinese E ngineering and M ining Com pany for th e y ear to J u n e 30 last show th a t th e profit of th e K ailan M ining A dm inistration am ounted
to $4,064,030, th e am o u n t due to th e com pany being $2,363,294. T h e reduced profit is due to a restric te d o u tp u t of coal caused b y tro u b le w ith th e Peiping-Liaoning railw ay, th e sales a t 4,500,000 tons showing a reduction of 251,000 tons com pared w ith th e previous year. T he profit of th e com pany for th e y ear was £142,153, th e balance available being £146,041. Incom e ta x absorbed
£98,098, leaving £47,942 for d istrib u tio n . B y bringing in £2,500 from reserve, a dividend of 2 J% w as paid, absorbing
£49,000, and a balance of £1,442 carried forw ard.
P a n a m a . — Shareholders of P an am a C orporation have been inform ed of develop
m e n ts in th e E l M ineral d istrict a t M argaja, w here a lode intersected a t 80 ft. below th e surface assays $92 over 36 in. T h e sam e lode 13,000 ft. aw ay assays $108 over 27 in. I t w as su bsequently announced th a t in view of developm ents on th e co m pany’s properties th e an n u al re p o rt h as h a d to be postponed u n til F eb ru ary .
B o liv ia .—A t a special m eeting of P a tin o Mines and E n terp rises to be held th is m o n th it will be proposed th a t th e com pany should acquire in exchange for shares n o t less th a n 90% of th e cap ital of Sociedad E m p resa de E stan o de A raca.
M exico.—A t a m eeting of E sp eran za, L td ., held th is m o n th it was resolved th a t th e com pany should go in to liquidation.
S p a in .— Shareholders of Tigon Mining and Finance Corporation were inform ed last m o n th th a t th re e u n its for tre a tin g ore have now been co n stru cted a t th e Spanish properties and four others are to be bu ilt.
I t is sta te d th a t th e p ro d u ct finds a read y sale locally. In Chile recen t inroads in to stocks have m ade it necessary to p rep are for an early resum ption of sulphur production.
I t is sta te d th a t th e cash resources of th e com pany are am ple to cover th e program m e on h an d
Y u goslavia. — A t an e x trao rd in ary m eeting held la st m o n th it was resolved th a t th e cap ital of Zletovo Mines be increased to
£185,000 b y th e creation of 140,000 new 5s. shares.
R u sso -A sia tic C o n so lid a ted . — T he accounts of Russo-A siatic C onsolidated for th e year to Septem ber 30 la st show a profit of £584, th e d eb it balance carried forw ard being reduced to £1,469. T he position as regards th e R ussian in te rests of th e com p a n y are held to be m uch as th e y were a y ear ago.
By E. J. W AYLAND, A.R.C.Sc., F.G.S.
The author, who is Director of the Geological Survey of Uganda, gives an account of the geology of the Protectorate in relation to mineral deposits and water supply.
I n t r o d u c t i o n . •— U ganda is a B ritish P ro te c to ra te bordered on th e north-east and on th e w est by rift valleys, and on th e south
east b y Lake Victoria, an immense fresh
w ater lake com parable in area w ith Scotland, a n d situ a te d on th e p lateau of east-central Africa. The P ro tecto rate is divided into four provinces : th e E a stern Province, w ith h ead q u arters a t Jin ja, and district head q u arters at Jin ja , Mbale, B ubulu (south
east Elgon), Soroti, Lira, Kitgum , and Moroto ; B uganda Province (U ganda proper) w ith head q u arters a t K am pala an d district h ead q u arters a t K am pala, E ntebbe, M asaka, an d M u b e n d i; th e W estern Province w ith h ead q u arters a t F o rt P o rtal an d district head q u arters a t F o rt P ortal, M barara, and K e g e z i; an d th e N orthern Province w ith h ead q u arters a t Masindi, an d district head
qu arters a t Masindi, Hoima, Arua, an d Gulu.
The cou n try forms p a rt of th e G reat African peneplain, the developm ent of which in th is area, in spite of th e existence of a few residual hills, h a d reached a very high stage of perfection before elevation to form th e present plateau subjected it to th e gouging action of consequent stream s, whereby it was dissected into a num ber of flat-topped hills. These hills, separated by wide papyrus-choked swamps, or more or less dry, flat-bottom ed valleys, are highly typical of th e scenery of U ganda proper ; b u t th e rifts, th e u p th ru st mass of Ruwenzori an d th e volcanoes have a grandeur of their own, an d the more northern p a rts of the te rrito ry are represented by a relatively low- lying plain supporting ra th e r short grass and scattere d bush.
U ganda is essentially open country. About 2% of th e area only is under dense forest.
W hat forests there are te n d to occur near th e lakes, on th e islands in Lake Victoria, and on th e m ountains. L inear patches of forest occur in a num ber of th e stream - bearing valleys and th ey are in m any places separated by savannah, which also tends to occupy broad, flat, dry valleys th a t have recently been swamps. The central portions of th e country, except where artificially cleared, are densely covered w ith elephant grass which grows to more th a n twice the height of a m an. Much of th e south-w est
is alm ost bare of vegetation, except for short grass on th e hills an d p apyrus in the valleys.
The highest general level of th e P ro tec
to ra te is in th e south-w est, where th e average a ltitu d e exceeds 5,000 ft., and m uch of th e area lies above 6,000 ft. The lowest general level is in th e north-east where, except for a fringing of relatively elevated land exceeding 4,000 ft. an d rising in places to m uch greater heights, th e average altitu d e is not m uch above 3,000 ft. The highest point of th e P ro tecto rate is M argherita P eak (16,794 ft.) on Mt. Ruwenzori, while th e lowest is on th e Nile near Nimule (1,930 ft.) where it passes into th e Sudan by way of a sudden bend and a rem arkable S.E .-N .W . stretch. The m arked tendency is for the highest country to border th e rifts.
Ruwenzori, which is alm ost surrounded by rifts, is the only m ountain in U ganda th a t has a perm anent snow and glacier field.
The volcanoes of B ufum bira (M uhavura 13,547 ft., Sabinyo 11,960 ft., and Mgahinga 11,400 ft.), to th e south of Ruwenzori, are p a rt of th e great B irunga volcanic area th a t lies a th w art the w estern rift ; an d Mt.
Elgon, another volcano (14,178 ft.), borders th e eastern rift, which is in K enya.
The m ean annual rainfall of th e P ro tecto rate varies from less th a n 25 in. in K aram oja (N.E. Uganda) to about 80 in th e Sese Islands. On Ruw enzori it is recorded as 65 or more, and on Elgon about 70 in.
The lakes of U ganda are all rem arkable ; th e y have h ad unusual histories, an d all m ay be said to owe their origin to secular disturbance. Lake V ictoria (26,828 sq.
miles, altitu d e 3,726 ft.) lies in a relative downwarp, or subsidence ; Lakes A lbert (area 2,064 sq. miles, altitu d e 2,028 ft.), E dw ard (area 830 sq. miles, a ltitu d e 3,000 ft.), and George (area 114 sq. miles, altitu d e 3,015 ft.), are all in th e w estern rift valley ; while Kioga (area about 2,000 sq. miles, altitu d e 3,376 ft.), alm ost unique am ong lakes, is a drowned valley system ; and there are other, b u t sm aller exam ples of this ty p e of reservoir (Fig. 2). In th e volcanic area of th e extrem e south-w est of th e P ro tecto rate there are a num ber of lakes th a t, as A. D.
Combe has shown, owe th eir origin to th e 9
10 * T H E M IN IN G MAGAZINE
Fi g. 1 .
Fi g. 2 . — La k e Na k a v a l i—a t y p i c a l s w a m p l a k e f o r m e d i n a d r o w n e d E R O S IO N V A L L E Y , L A R G E L Y F I L L E D W IT H P A P Y R U S A T T H E P R E S E N T D A Y .
dam m ing of erosion valleys by lava flows (Fig. 3).
G e o l o g y a n d M i n e r a l s .— I t is not enough to say th a t U ganda is p a rt of the great African table-land, for a stu d y of the plateau x shows th a t these do not represent a single g reat erosion-cut surface, b u t three such surfaces, three peneplains in fact, now
elevated to form th e tab led uplands of Central Africa. Though all m ay be present in an area, th e highest and oldest of these is best seen in Ankole, the middle and younger is typically developed in B uganda, p a r ti
cularly E astern B uganda, and th e th ird and youngest in the north ern and n orth-eastern p arts of th e P rotectorate. Econom ically
Fi g. 3 . — La k e Bu n y o n y i—f o r m e d i n a n e r o s i o n v a l l e y d a m m e d b y a L A V A -F L O W , W H IC H O C C U P IE S T H E F O R E G R O U N D .
12 T H E M IN IN G MAGAZINE th e y are extrem ely im p o rtan t, a n d th e y will
be considered a t g reater length later. T hey cu t across all th e solid rocks except th e la te r volcanics (Fig. 14).
The d istrib u tio n of th e various m em bers of th e stratig rap h ic al groups present will easily be seen from th e accom panying m ap (Fig. 1). A few w ords ab o u t each of these will be necessary.
The Basement Complex consists of th e u sual assem blage of gneisses, schists, q u art- zites, and occasional lim estones, an d does n o t call for an y special description here
(Figs. 4 and 5). I t is, in p a rt a t any rate, a highly m etam orphosed sedim entary series of v a st an tiq u ity , an d is ap p a ren tly in tru d ed b y a charnockite series, strikingly sim ilar to th a t of India. R esearch upon these rocks is proceeding. The Complex is, of course, pierced b y all th e various subsequent intrusives, including th e highly im p o rta n t Newer G ranites, a n d th e dolerites, m any of which are probably of K arroo age.
A p art from some valuable lim estones and m ag n etite deposits in and derived from th e lim estones, no m inerals of economic im portance are, a t present, definitely know n to occur in th e rocks of th e Complex, except in Ruw enzori, where copper ores an d galena have been introduced into th em by la ter intrusion.
A t K ilem be (N. 0° 12', E. 0° 30', approx.), in a sm all trib u ta ry valley of the N am w am ba River, on th e south-east of Ruwenzori, T a n g an y ik a Concessions, L td ., are developing
a prom ising copper deposit. T he copper m inerals know n to occur th ere are chalcopy- rite, chalcocite, chalcanthite, an d cupriferous pyrite, in th e u n w eathered or b u t little w eathered r o c k s ; an d m alachite, azurite, chrysocolla, m elaconite, a n d cu p rite in th e oxidized zone. T he co u n try rocks are m etam orphic. T he m ajo rity are hornfelses consisting, for th e m ost p a rt, of v ery fine aggregates of q u artz, sericite, an d am phibole ; th e accessory m inerals being iron ores, copper ores, blue tourm aline, an d chlorite.
The hornfelses were pro b ab ly derived from
sedim entary rocks, which, judging by th e large q u a n tity of am phibole usually present, have been subjected to high te m p eratu res an d g reat pressures. Some schists occur, an d asbestos is also present.
There are several form s of in tru siv es.
Among these m ay be m entioned a not-very- com m on th u lite-b earin g rock. T his is in tru d ed into a talc-schist an d is p in k in th e h a n d specim en. In th in section th e rock consists of tu rb id plagioclase, m uch m angani- ferous zoisite (thulite), a n d a v ery sm all am ount of secondary in te rs titia l q u artz.
The age relatio n sh ip of th e p in k rock to other intrusives is n o t definitely know n. A very early intrusive, now sheared, is a m uscovite-biotite-granite, while la te r come am phibolites and epidiorites. T he n ex t in order of appearance w ould seem to be an alaskite of (in places) p eg m atitic coarseness.
I t is of special in terest because it carries copper sulphides—m ainly ch alco p y rite. In
Fi g. 4 . — A Ty p i c a l Is l a n d- Mo u n t o f Ba s a l Co m p l e x Gn e i s s i n Ka r a m o j a.
th in section it is seen to consist of ta tte re d crystals of tu rb id plagioclase (probably oligoclase) showing fine tw in lamellae ; much crushed q u artz w ith crenulated borders, and in te rstitial strongly m ylonised q u artz and felspar. Tourm aline is also developed, and in some specimens is fairly abundant.
C utting th e other intrusives is a dolerite.
No. 1 adit is driven into this rock, which in th in section is v ery similar to dolerites intrusive into th e sedim ents of th e B ukoba sandstone series (vide infra). W hen fresh, th e pyroxene is practically colourless, b u t easily develops brow n pleochroic m argins which steadily grow inwards, th e crystal at th e same tim e becoming pale green in the m iddle. The brown afterw ards changes to
are certain phyllites an d sheared con
glom erates occurring on Ruwenzori. They are probably paralleled in a n tiq u ity by others on th e eastern side of Lake V ictoria in K avirondo (K enya Colony).
Succeeding th e Complex (and probably th e conglom erates just m entioned) is an im p o rtan t system of phyllites w ith quartzites and conglom erates known as the Karagwe Ankolean (referred to for convenience as K.A.) (Fig. 6). The deposits are of great thickness and are presum ed to rest unconform ably upon the older rocks, b u t no u n d oubted junctions w ith them have been seen. The K.A. rocks have been throw n into a very complex series of pitching anticlines, syn- clines, and overfolds, and p a rt of th e move-
F ig . S.— Gn e i s s e s o f t h e Ba s a l Co m p l e x In t r u d e d b y a Do l e r i t e Si l l.
green, an d by the tim e the whole crystal has become a deep bluish-green it has been transform ed into am phibole. The labra- dorite is fairly fresh and there is much in terstitial m icropegm atite, quite sufficient, in fact, to call this rock a grano-dolerite (Shand). The usual accessory ilm enite and leucoxene are present.
The copper m inerals occur more in the country rocks—th e hornfelses and schists—
th a n in th e alaskite, and appear generally to be im pregnations more particularly along th e cleavages and schistosity. So far as it is known, th e stru ctu re of th e cupriferous area appears to be essentially synclinal.
It is also faulted.
Associated w ith the Complex, b u t app aren tly younger th a n th e mass of it,
m ent which produced these results was associated w ith th e intrusion of th e Newer Granites, th e apophyses of which have yielded m ineralizing residuals th a t have produced th e tin lodes of the south-w estern areas, an d in th e adjoining territories of T anganyika, Belgian U rundi, and R uanda.
Ripple m arks are of common occurrence in the quartzites, which persist for astounding distances, and locally th e phyllites show beautiful banding, which on expert exam ina
tion proves to be of seasonal origin (Fig. 6).
The K.A. rocks appear to have accum ulated on the slowly sinking bottom of a vast inland basin, com parable in size to th a t of Lake Victoria, b u t th eir lithology and d istribution raise m any problems. R epeated search and close study of the K.A., m ade
14 T H E M IN IN G MAGAZINE over wide areas, have failed to reveal
th e slightest trac e of fossil rem ains, a n d for th is reason, an d on account of th e ir obvious a n tiq u ity , th e y are assum ed to be Pre- C am brian in age. A nother area (a sm all one, ab o u t 600 sq. miles) lies to th e east an d so u th east of th e K asinga c h a n n e l; a n o th er w ith a m ark ed silicious facies exists around M ubendi, a n o th er near Jin ja , a n d still an o th er in Sese Isles.
Some rem arkable iron ores are provided by haem atite-schists, containing a little m agnetite, interbedded w ith th e K aragw e- A nkolean phyllites, p articu larly in th e Kigezi district. T hey reproduce in replica all th e fine stru ctu res of th e phyllites, a n d are clearly due to replacem ent. Locally these ores are v ery ab u n d an t, a n d for such massive deposits th e y are astonishingly pure. The following are analyses of th ree sam ples m ade by th e Im perial In stitu te .
F e rric O xide ( F e ,0 3) F e rro u s O xide (FeO) A lu m in a (A120 3) . T ita n iu m O xide ( T i0 2) Silica (S i0 2)
S u lp h u r (S) P h o sp h o ro u s (P) . L oss on ig n itio n .
The localities are as follows :— (1) N ear K abale, W estern Province ; (2) N ear Kigezi, W estern P ro v in c e ; (3) Jo k a n a E sta te , near K am pala, B uganda Province.
No. 1.
0/ N o. 2.
0/ No. 3.
/o 0/
98-88 97-41/o 96-37/o
0-16 1-26 2-98
0-08 0-78 0-13
N il Nil Nil
0-40 0-94 0-38
N il 0-004 0-004
N il 0-006 0-009
0-28 0-17 0-33
U nfo rtu n ately , th e difficulty of securing sufficiently large a n d accessible m ark ets, and of good inexpensive fluxes a n d fuels stan d , for th e present, in th e w ay of developm ent of these rem arkable deposits. N ativ e sm iths, however, m ake considerable use of th em in some p a rts for th e m an u factu re of hoes, spears, an d knives (Figs. 9 a n d 10).
W est an d south-w est of M asindi, in B unyoro, an d to th e east of th e Nile where it leaves L ake Kioga, is an o th er great developm ent of phyllites, phyllitic shales, m udstones an d quartzites, w ith calcareous horizons, closely resem bling th e K aragw e A nkolean rocks in m an y of its features. I t is on th e whole, less m etam orphosed, however, an d less obviously in tru d ed by granites. I t was a t one tim e spoken of as th e B unyoro facies of th e K.A., b u t its contem poraneity w ith th e phyllites of th e south is m uch open to question, an d it is doubtless b e tte r to speak of th is developm ent as th e Bunyoro Series. F rom w h at is know n of it, it appears to have suffered less folding th a n th e K aragw e Ankolean, an d has been considerably affected by faulting, m ainly in two directions : One ap p ro x im ately n o rth an d south, an d th e oth er ap proxim ately east an d west. I t is, in fact, considerably block-faulted. Included in th e lower p a rts of th e sequence is an im p o rta n t tillite wrhich closely resem bles th e N am ees tillite of N am aqualand, w ith w hich it is possibly contem poraneous. There are, too, some
Fi g. 6 . — K . A . Ph y l l i t e s, s h o w i n g s e a s o n a l b a n d i n g, n e a r Ka b a l e, Ki g e z i Di s t r i c t.
