Show MINING GOLD IN COLOMBIAN RICH ALLUVIAL DEPOSITS the most promising gold fields are those where monitors and hydraulic elevators can be installed and operated by modern methods by dr mariano ospina perez ME CE A ALTHOUGH a great deal has been said in the past about the vast mineral wealth of columbia and the excellent prospects of the gold mines which require development in the near future their possibilities have not yet been fully realized by the majority of the people abroad the most promising results are obtained from the gold allu vials no other country in the world enjoys more favorable conditions for the formation and concentration of large zones of auriferous allu vials the territory of colombia particularly the department of antioquia and the province of choco and also the departments of toli 1 41 N P FL 0 W bixl ixl az PACIFIC 1 C L 0 X 4 map of colombia the darker area indicates where alluvial gold deposits are located la a bolivar caldas and cauca are crossed in all directions by y rich auriferous reefs but the country is very mountains ous and has numerous rivers which in a previous geological age were much larger than now and the effects of erosion have been of considerable magnitude during the quaternary period colombia also expended experienced the three general movements of the soil which occurred in europe and in north america the first rising occurred during the glacial period and coincided incited inci ded with the enormous increase which took place in the volume of the waters when a great mass of decomposed and d broken rocks must have drifted toward the valleys at Octo bar campania mancra de colombia in the du pont font magazine for carrying the 6 gold from the auriferous deposits in the reefs and veins bro broken ken up by this geological movement during the period of the terraces when the new elevations of the continents took place subsequent to the lowering in the champlain period a concentration was registered in the great deposits of gold disseminated in the mass of rock causing the formation of the rich allu vials now exis existing tincy 6 in colombia which are probably the richest in the world one pound of gold per square yard franklin white an english mining engineer who for eight years was managing director of the gold mines mine s owned by the bolivia and frontino mining company ltd of london said in 1883 referring to the nechi river river in the department of antioquia if this river is properly dredged the 6 gold extracted will greatly exceed in quantity the entire production of australia although I 1 am only venturin venturing an estimate I 1 believe the river nechi will yield tons of gold old along the fifty mile course separating DOS bosas from the cauca river the above estimate apparently very optimistic is based on a working width along the course of the river of feet and corresponds to a yield of grammes gramm esper per square yard in spite of the high figure attained from the above data mr white insists on the accuracy of his statement which aich is to some extent confirmed by the favorable results obtained in numerous dredging operations carried out in the borce and nechi rivers as shown by the following examples in the erea dredged by the pato Coni company pany an eng ish enterprise at pato the results have proved that the river bed contains grammes per square yard the operations carried out at charcon have resulted in a yield of grammes of gold per square yard of river bed mr white also states that along the force river there are many places where the y yield beld per square yard is onan on an average grammes such as las palmas Guay Gua abrl guayabalito Guayaba lito colorados Or alito poca pedrero socorro and many others it must be remembered that a great many of the experiments peri ments carried out by mr white took place during the dry season with the aid of natives and employing very rudimentary methods his estimate may in av be somewhat exaggerated although it is based on data properly ascertained but in any apse case it gives an idea of the prospective wealth of the alluvial sands occupying the beds of these rivers there are other rivers equally rich and equally suitable for profitable working in the vast territories of antioquia caldas bolivar and choco 67 fit z f low A in the force river work is iq conducted to exploit the ancient river bed then the river is run through the holes made and the actual bed is worked advantages of alluvial mining the working of alluvial gold mines is a very ness proposition it has a great many advantages over other mining operations with the aid of modern drills worked either by hand or steam it is an easy task to make a close examination of an alluvial deposit at comparatively small cost and within quite a short time it is said that an alluvial deposit properly examined is a gold bar in alluvial mining the risks of speculation are considerably limited in a factory in produce or cattle raising the balance sheet is influenced by the fluctuations of raw materials trade depression heavy competition and many other factors which do not affect the gold market where the fluctuations are small or affect the actual working operations on the river bed once the t e amount of gold contained in the sands has been ascertained certa ined no fears a as to the destruction of the mineral wealth can be entertained and it becomes a matter of time and machinery to turn into account the rich contents content s with modern moden installations it is easy to predetermine the number of cubic yards worked per month and the working costs per cubic yard knowing from the examination what the average yield is it will not be difficult to make a forecast of the probable earnings safety for investors the working of the alluvial gold deposits of colombia will probably attract during the next thirty years as much attention and employ as much capital as her great oil deposits which have of late brought the country to the fore as a first class prospective oil producing territory this statement may sound to some of our readers somewhat exaggerated but we have sufficient knowledge of existing conditions to support our view low operating operate n g costs in addition to the safety of alluvial gold mining as a business proposition there is another great advantage the value of which is of paramount importance in these kinds of enterprises we refer to the very few experts and work men required labor is an important factor in every industry in view of the high salaries prevailing and the ever increase increasing ing demands of the trade unions in n all alluvial civial minin mining g nearly all the work is done by hydraulic or hydroelectric power ii 41 another great advantage that colombia offers for the economical development of alluvial gold mining is the considerable number of large waterfalls suitable le it I a sm small all cost for hydroelectric power p plants hafits tosu to su supply I 1 y the dredgers the water supply is indeed very p jiz ful and can also be used to work monitors and 6 hydraulic elevators the natives and the spaniards worked only the surfaces of the veil veins is and reefs and the alluvial Ws of small streams the machinery and appliances for exploiting on a large scale being absolutely unknown in in their time primitive and rudimentary methods were used in the production of gold in colombia during the past four centuries and records indicate that the yield for the bhole whole territory during that period was wa expressed in round figures as follows in the centar century y t lath total A A an alluvial mine in antioquia where a hydraulic elevator is working in cOmbi nAdOn with a note the large boulders the gold extracted from the mines in the Dep artnie ent of f antioquia was approximately as fol follows ionas I 1 inthe in n the century ad half 1 it it it i it 1 L total the production for 1921 was about 50 00 in the sanie same department which is the richest in i minerals in the country countr 3 owing to civil wars which prevailed in colombia during in I 1 the past century the mining industry w was as kept almost undeveloped particularly the alluvial gold deposits referred to the past twenty years have registered wonderful results in the gold mining industry of the country due partly to the use of modern machinery and partly to the peace enjoyed during 6 the same period we have now a stable government and the possibilities of an internal disturbance tur bance are very remote monitors and elevators in 1870 the first monitor brought to south america was installed in the malpaso malpass Mal paso in the department of tolima bolima in 1880 a company was formed in the united states to dredge along the atrato airato river the company was very unfortunate at the commencement of its operations its first dredge sank in the atrato airato river and the second was so seNe severely rely damaged that it soon became useless today there are several dredges working iv successfully in different parts of the country but it is evident that the most promising gold fields at present are those where monitors and hydraulic elevators can be installed not only owing to the reduced cost of plant and running expenses but also in view of the greater yield usually derived from the alluvial deposits situated in the high er levels closer to the gold veins and with a higher concentration cent ration per square yard the departments of antioquia and caldas and the province of choco offer exceptional opportunities in this respect the first hydraulic elevator was installed in the borce river some twenty years ago during the past ten years several companies have established hydraulic elevators in this river and the results have been highly satisfactory with all of them in the mine known as hormiguero a 12 inch elevator has produced in two months ounces of gold and frequently similar elevators each give a yield of ounces of gold per month at a cost not exceeding 2500 other plants are now in course of erection in other rivers in the department of antioquia nearly all these hydraulic mining installations are situated in the force river in view of the transport facilities available the region being also thickly populated and 14 va s 2 near the important town of our p personal personal knowledge together with information we have been able to collect from very reliable sources leads us to believe that in the rivers of the departments on antioquia caldas and bolivar and the province of choco there is ample room for more than installations of monitors and hydraulic elevators with very good prospects for successful development we have devoted special attention to the study of the alluvial gold old deposits of colombia so as to be in a position to make such a bold statement v j W 7 ot V the inset inget A hydraulic elevator and hydraulic giant in a mine on the borce river towards lombolo bolombolo Bo looking up the cauca river |