THE WORLD'S GREATEST MINE STEWART J. LLOYD University of Alabama, University, Alabama
FORT KNOXis an interesting place to visit, and so is the Bank of England, and so are the mile-deep gold mines of the Rand, but no one of them contains the world's biggest lump of gold. That honor is held by the ocean, the world's greatest mine of gold and most other metals. The ocean carries enough gold to make a cube 240 feet (a little less than one-twentieth of a mile) on an edge. This gold would weigh eight and one-half million tons and would be worth today a t $35.00 an ounce over seveu.thousand billion dollars. Six years of war with 30-million men throwing steel and copper and lead a t one another took a heavy toll of the world's minerals. Mines were robbed of their richest ores-iron ore for steel, bauxite for aluminum, copper, lead, and tin ores for auxiliary munitions. Mica, quartz, molybdenite, tungsten, beryllium, etc., deposits were removed. So thoroughly were some mines depleted that metallurgists began to fear a permanent scarcitv of some of the world's common metals. If the backw&d nations, backward industrially, begin to use metals like the forward ones, the scarcity will apparently come soon, war or no war. Mmerals do not renew themselves annually like cotton and wheat, nor do they grow like trees to be cut every 50 years. When they are gone, they are gone, except for what is recovered in the form of scrap and used and reused again. Where are we going to get our metals or their ores when our present mines give out? OUTCROPPING MINES
There are two places where we'can properly look for them. Our gold, copper, lead, and other mines of today were practically all found because the ore ledges stuck ' out of the surface of the ground where people could see them. Someone threw a rock a t a wandering burro in Idaho, noticed that it (the rock) was extra heavy, and discovered the famous Coeur d' Alene lead deposit. Copper veins often have a rusty or green colored look on the surface, and many a lucky prospector has felt the matchless thrill of seeing little specks of dull gold in the white quartz he has broken off from the outcrop of a 'vein. The red iron ores of the Birmingham Valley in Alabama were easy to see, and even the Indians knew they were something out of the ordinary. But there is reason to believe that plenty of other large deposits exist that do not show a t all on the surface. A few of these have been found, purely by chance, when drilling for water or some other purpose. HIDDEN MINES
Oil and gas, on the other hand, rarely show on the surface, and to find them we have had to devise means
of "seeing under the ground." The oil men call this "geophysical prospecting." Half a dozen different devices are u-ed-seismographs (artificial earthquakes), magnetometers (sensitive magnetic needles), gravity meters, and geochemical, electrical, and radioactive methods. These devices are being applied now to other minerals, not just oil and gas, and we ought to have the same successful results here as in the oil industry. Indeed, a Russian named Lukisky has recently worked out a new method of locating mineral? hidden very deeply underground. There are probably just as many good ore bodies completely hidden underground and waiting for exploitation as we have found outcropping a t the surface. THE OCEAN
But besides all this n p have a mine all ready and prepared for us, with the ore analyzed, the composition fairly uniform, and the quantities really unlimited. No land to buy, no expensive prospecting, no shafts, no tunnels, no costly ventilation systems, no timbering. A suitable location on the sea coast, pumps, a process not too costly for extracting the metal from the water, and we are all set. The ocean is the world's greatest mine. How many tbus of water are there in all the oceansthe Atlantic, Pacific, Indian, Arctic, and Antarctic? Well, there are about 300-million cubic miles of ocean, and each cubic mile contains 4.75-billions tons of water. If we multiply these two figures together we get 14.25 X 10" tons for the weight of all the sea. How t o express this number in words is a puzzle. Thk next thing to learn is: How many pounds of the different metals and other materials are found in one ton of sea water? A few of these figures are given below, starting with the largest. Most of them are approximate only. A short ton (2000 lbs.) of sea. water contains about: Material Pounds Materid Pounds 55 O.OOM19 Common salt Iodine Magnesium 2.54 Iron 0.00004 ' Sulfur 1.75 Copper 0.00002 Calcium 0.8 Lead 0.00001 Patrusium 0.75 Zinc 0.00001 Bromine 0.125 Uranium O.OOW03 Strontium 0.025 Silver 0.0000006 .0.008 Gold O.OOOOOW12 Boron Radium 1 X 10Fluorine 0.0025
The entire ocean holds, therefore, to take a few examples, 4 X 1018tons of salt, 2 X 1015tons of magnesium metal, and 9 X 10Ia (ninety-thousand billion) tons of bromine. The world uses now about 30-million
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tons of salt a ykar, only 275,000 tons of magnesium, and 60,000 tons of bromine. Evidently we are not going t,o run out of these materials soon. And better still, the magnesium andbromine and salt are not lost by use, but go back to the earth in one way or another and by slow degrees find their way again into the ocean. The rains have been leaching these materials in one form or another from the earth and carrying them down into the sea for millions of years, and man is merely helping in his feeble'way. From where did the ocean get its salt, magnesium, bromine, etc.? Water is a wonderful solvent, and warm rains soaking into the earth dissolve a lot of things, carrying them slowly to the nearest stream, then to the nearest river, and finally down to the sea. When the sun "draws water" from the ocean, it draws pure water and leaves these things behind, and the pure water, as clouds. moves over on the land. descends as showers., and leaches more salt and hrombe and magnesium to go down to the ocean. The ocean should he getting &her in salt and other minerals, but man has n i t been watching i t long enough to notice any real change.
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other solids that were in the water, not a very palatable salt indeed, but good enough for preserving fish and capable of further purification. Only warm sunny coasts with a low and predictable rainfalllendthemselves to this. North Africa and San Francisco Bay are examples. Solar salt is still made in large amounts on our west coast. The American Civil War had one salty episode little known today. There were shortages then as in 1944, hut of different things. Salt was desperately scarce in the Confederacy although the South is now rich in salt, and salt black markets, while not so called, flourished widely. Small plants t o make salt by evaporating sea water were set up along the Florida coast, especially in St. Andrews Bay (near Panams City), and every now and then Federal gunboits would sail into the Bay, shoot up these plants, and depart t o make another visit I%~PP. ------BROMINE AND MAGNESIUM
They who go down to the sea for chemicals will ever remember the name of H. H. Dow, the founder of the Dow Chemical Company. Coming to the United States from Belleville, Ontario, he started a small plant VARIABLE COMPOSITION a t Midland, Michigan, where deep wells had reached a Is the composition of the ocean the same everywhere? flow of mineral water that held notable amounts of magApparently not, as evidenced by the story of Fritz nesium, bromine, and many other elements. Bromine Haber, the famous German chemist, the originator.of was his object, and he soon became a major producer of gas warfare, and the discoverer of low-cost nitrogen this useful substance. But the other things in the fertilizer. Haber was a patriotic German who saw mineral water were going to waste, which did not please Germany crushed under a postwar load of reparations h i a t all, so one by one he began to find uses for them. after World War I. How were these to be paid? If it From salt in the brine he made caustjc sodaand chlorine; were possible t o extract profitably the gold known t o t o find a use for phlorine he made chlorbenzol, and t o be in the ocean, an easy way of paying the debts withuse his caustic soda and chlorbenzol, he made phenol out burdening German economy was a t hand. With (carbolic acid) from them by a new process. The the aid of the Hamburg-American Steamship Company magnesium in the water was another loss, so be began he set to work and perfected a way of extracting the to see how it could he extracted. Magnesium was then gold from a synthetic, artificial sea water. But when a rare metal, sold by the ounce or pound, and sparingly sea water from many localities was~analyzedfor gold, used. It is lighter than aluminum, and if cheap enough, the amount turned out to be quite variable, Apparently would be a valuable structural material for aircraft as the gold is not dissolved in the sea water but is merely well as a useful incendiary for firebombs. floating in it. Nearly everywhere it ran far below the Soon lead tetraethyl, the anti-knock material in ' figures given by earlier scientists, and only in two ethyl gas, which calls for bromine in its manufacture, places were figures obtained that offeredany hope. One was discovered. The demand for bromine jumped fourof these was San Francisco Bay, the other the tumul- fold. Efforts were made t o extract it from Atlantic sea tuous seas that lie between Newfoundland and Lab- water in a floating plant, the good ship "Ethyl." But rador. So Haber kave it up, remarking a t the end of later the Dow Company and the du Pont organization the description of his work that there might be enriched joined forces in a land plant on the Carolina coast near areas where gold mining of sea water would pay hut Wilmington where the major part of America's bromine. that he was not going to look for such a "needle in a , was for some years extracted from the cold waters of the haystack." Whether future ocean prospectors will Atlantic. Later during the war a similar plant.was accept Haher's word as final remains to be seen. built a t Freeport, Texas, near the magnesium installation. Here surely is one company that need never SALT worry about the exhaustion of its raw material. The start of the war found the Dow Chemical ComThe first mineral to be mind from sea water was undoubtedly salt. Both animals and men crave salt, pany the sole producers of the metal on this continent. although Stefansson, the Arctic explorer, claims we can Their capacity a t Midland, where they took it from all get along without it if we have to. If we trap sea deep well waters, was far too small to supply the United water when the tide rises and let the hot sun work on it States in a war, not t o mention the Allies. And no one t o evaporate the water, we get "solar" salt with all the else had the "know how." Hence their whole experi-
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ence was placed a t the disposal of Uncle Sam, and a huge plant built near Houston on the Gulf of Mexico where sea water, much poorer in magnesium than the Midland wells, became the raw material. Remember that one ton (2000 lhs.) of sea water holds only two and one-half lbs. of magnesium. Oyster shells to make lime, salt to make chlorine, natural gas to produce electric power all had t o be provided for the process. A1though other and probably more expensive ways of making magnesium were also put, into practice, including Kaiser's plant at Permanente, Ca1ifornia:tbis tremendous Dow plant in Texas was the backbone of the nation's magnesium supply. Plenty of the metal for air craft and incendiaries was made and, as an antiCourtesy of the Dow Che>n~cnl Company climax, the Dow Chemical The Dow Megnerrivm PLant at Freeport. Texas. Is s e e n Above. The Circular vets o n the Left Are Company was promptly at- the Dorr Tanks in Which Sea Water Iq Reacted wEth Slaked Lime to Resipitate Magnesium Hydrate. Beyond These A m Pilea of Oyster Shells end t h e Two Long Rotary Kilns in Which Thsy Are Burned to tacked by the Department Lime. To Thsir Right Are t h e Moore Filter for Filtering o u t Magnaium Hydrate and Evaporator. Whe.. of Justice because in prewar Megnesium Chl01ids Liquor Is Concentrated end Mamerium Chloride Extracted i n Flake Form for Cell years it had exchanged data Feed. Th. Long Black Buildings in the center Are t h e Cell Buildinrn Whoro Metallic Magnesium I. Extracted from the Magnaium Chloride. I n tho Left Bqkrnound Is the Ethyl-Dou Plan, Where Bromin. with foreign companies. Is Taken from Sea Water and Converted into Ethylene Dihromide for Addition to Anti-Knock Gasoline. Many chemical industries use salt as their raw material, especially the alkali and chlorine industry, and of abstracting certain materials from the soil and the in Scandinavia sea salt has served as a starting point for water and storing them up in their own tissues. The soda ash. So we may say that satt, magnesium, bro- horse tail (equiselum) takes up silici and gold, the loco mine, and soda are products of the sea jqst as surely as weed takes up barium, while certain sea meeds pick u p from the sea water large amounts of potassium and oysters. iodine. When the weeds are burned these elements are OTHER ELEMENTS left in the ashes. This used to be the commercial way But what about the other elements? How about of getting these two substances. Copper, zinc, barium, gold, copper, silver, potash (for fertilizer), boron, and and many other elements have also been detected in especially uranium. A ton of sea water holds very little the ashes of sea plants. Sea animals (oysters) remoye of any of these, hardly enough to make us go after them calcium carbonate from the ocean to make themselves directly. Is there any hope of getting gold and uranium shells, and lime and cement are produced in many and iodine, etc., from the ocean without going broke in places from these shells. Why not, then, in some sheltered bay deliberately cultivate sea plants which doing it? Well, Fritz Haber, as already mentioned, thought it absorb the wanted element, boron or beryllium perhaps, worth trying for gold, but did not quite make a success harvest them periodically, and recover the metal. What of it. Salt, magnesium, and bromine--numbers 1, 2, is needed is a thorough study of aquatic plants to see and 6 on our list-are already being mined, but what what they will pick up and perhaps the development of about 3, 4, and &sulfur, calcium, and potassium? new varieties, just as we have produced strains of sugar It may be too expensive to extract these directly in beets with high sugar content. Uranium: But uranium is the interesting element comparison with present land methods, but mention today. The ocean contains three Ibs. of uranium t o of potassium suggests another way. If direct methods fail, we can fall back upon indirect every hundred pounds of iodine, and iodine is easily ones. Plants, both land and sea, have the curious power extracted from certain sea meeds-indeed, that is where
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it ll,as discovered, The ---mnch uranium as it doe, tons. Of this no doubt total) is uranium-235, eno of the world for aeons to cc I s i t not possible that sl may be found or develope~ from sea water and there Indeed the extraction may isotope will be more easil It is veil knoivn that cer gypsum, are richer in "he, tap water. This is a pro tried out in one of our ocea Jolla, Woods Hole, or Frid
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and dirigibles will soon be common practice and should add a lot to our food supolv. . > "~ Also complex organic acids are coming from the .giant seaweed (kelp) along the coast of British Columbia and California. Photosynthesis, the chemical re-
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action we'have not yet been able to duplicate in the laboratory, goes on in the upper layers of the ocean just as on land, and if the world population continues to increase as it has in the last half century, we are going to need all the help the sun can give us in providing food for it.
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The great civilizations of the world, the intellectual and aesthetic advances, have all occurred close to the sea coasts, not on the steppes and high plateaus of the continental interiors. If we make good use of the riches of the ocean, the coastal strip may likewise be the seat of the world's material wealth.
