| Country. | Workable Deposits. | Annual Output. | Annual Consumption. |
| tons. | tons. | tons. | |
| United States | 1,100,000,000 | 35,000,000 | 35,000,000 |
| Great Britain | 1,000,000,000 | 14,000,000 | 20,000,000 |
| Germany | 2,200,000,000 | 21,000,000 | 24,000,900 |
| Spain | 500,000,000 | 8,000,000 | 1,000,000 |
| Russia and Finland | 1,500,000,000 | 4,000,000 | 6,000,000 |
| France | 1,500,000,000 | 6,000,000 | 8,000,000 |
| Sweden | 1,000,000,000 | 4,000,000 | 1,000,000 |
| Austria-Hungary | 1,200,000,000 | 3,000,000 | 4,000,000 |
| Other countries | 5,000,000 | 1,000,000 | |
| Total | 10,000,000,000 | 100,000,000 | 100,000,000 |
Note to Table.—Though this estimate seems to be near the truth as regards the British ores, it does not credit the United States with one-tenth, if indeed with one-twentieth, of their true quantity as estimated by that country’s Geological Survey in 1907.
52. What Constitutes an Iron Ore.—Whether a ferruginous rock is or is not ore is purely a question of current demand and supply. That is ore from which there is reasonable hope that metal can be extracted with profit, if not to-day, then within a reasonable length of time. Rock containing 2½% of gold is ah extraordinarily rich gold ore; that with 2½% of copper is a profitable one to-day; that containing 2½% of iron is not so to-day, for the sole reason that its iron cannot be extracted with profit in competition with the existing richer ores. But it will become a profitable ore as soon as the richer ore shall have been exhausted. Very few of the ores which, are mined to-day contain less than 25% of iron, and some of them contain over 60%. As these richest ores are exhausted, poorer and poorer ones will be used, and the cost of iron will increase progressively if measured either in units of the actual energy used in mining and smelting it, or in its power of purchasing animal and vegetable products, cotton, wool, corn, &c., the supply of which is renewable and indeed capable of very great increase, but probably not if measured in its power of purchasing the various mineral products, e.g. the other metals, coal, petroleum and the precious stones, of which the supply is limited. This is simply one instance of the inevitable progressive increase in cost of the irrecreatable mineral relatively to the recreatable animal and vegetable. When, in the course of centuries, the exhaustion of richer ores shall have forced us to mine, crush and concentrate mechanically or by magnetism the ores which contain only 2 or 3% of iron, then the cost of iron in the ore, measured in terms of the energy needed to mine and concentrate it, will be comparable with the actual cost of the copper in the ore of the copper-mines of to-day. But, intermediate in richness between these two extremes, the iron ores mined to-day and these 2 and 3% ores, there is an incalculably great quantity of ore capable of mechanical concentration, and another perhaps vaster store of ore which we do not yet know how to concentrate mechanically, so that the day when a pound of iron in the ore will cost as much as a pound of copper in the ore costs to-day is immeasurably distant.
53. Future Cost of Ore.—The cost of iron ore is likely to rise much less rapidly than that of coal, because the additions to our known supply are likely to be very much greater in the case of ore than in that of coal, for the reason that, while rich and great iron ore beds may exist anywhere, those of coal are confined chiefly to the Carboniferous formation, a fact which has led to the systematic survey and measurement of this formation in most countries. In short, a very large part of the earth’s coal supply is known and measured, but its iron ore supply is hardly to be guessed. On the other hand, the cost of iron ore is likely to rise much faster than that of the potential aluminium ores, clay and its derivatives, because of the vast extent and richness of the deposits of this latter class. It is possible that, at some remote day, aluminium, or one of its alloys, may become the great structural material, and iron be used chiefly for those objects for which it is especially fitted, such as magnets, springs and cutting tools.
In passing, it may be noted that the cost of the ore itself forms a relatively small part of the cost even of the cruder forms of steel, hardly a quarter of the cost of such simple products as rails, and an insignificant part of the cost of many most important finished objects, such as magnets, cutting tools, springs and wire, for which iron is almost indispensable. Thus, if the use of ores very much poorer than those we now treat, and the need of concentrating them mechanically, were to double the cost of a pound of iron in the concentrated ore ready for smelting, that would increase the cost of rails by only one quarter. Hence the addition to the cost of finished steel objects which is due to our being forced to use progressively poorer and poorer ores is likely to be much less than the addition due to the progressive rise in the cost of coal and in the cost of labour, because of the ever-rising scale of living. The effect of each of these additions will be lessened by the future improvements in processes of manufacture, and more particularly by the progressive replacement of that ephemeral source of energy, coal, by the secular sources, the winds, waves, tides, sunshine, the earth’s heat and, greatest of all, its momentum.
54. Ore Supply of the Chief Iron-making Countries.—The United States mine nearly all of their iron ores, Austria-Hungary, Russia and France mine the greater part of theirs, but none of these countries exports much ore. Great Britain and Germany, besides mining a great deal of ore, still have to import much from Spain, Sweden and in the case of Germany from Luxemburg, although, because of the customs arrangement between these last two countries, this importation is not usually reported. Belgium imports nearly all of its ore, while Sweden and Spain export most of the ore which they mine.
55. Great Britain has many valuable ore beds, some rich in iron, many of them near to beds of coal and to the sea-coast, to canals or to navigable rivers. They extend from Northamptonshire to near Glasgow. About two-thirds of the ore mined is clayey siderite. In 1905 the Cleveland district in North Yorkshire supplied 41% of the total British product of iron ores; Lincolnshire, 14.8%; Northamptonshire, 13.9%; Leicestershire, 4.7%; Cumberland, 8.6%; North Lancashire, 2.7%; Staffordshire, 6.1%; and Scotland, 5.7%. The annual production of British iron ore reached 18,031,957 tons in 1882, but in 1905 it had fallen to 14,590,703 tons, valued at £3,482,184. In addition 7,344,786 tons, or about half as much as was mined in Great Britain, were imported, 78.5% of it from Spain. The most important British ore deposit is the Lower Cleveland bed of oolitic siderite in the Middle Lias, near Middlesborough. It is from 10 to 17 ft. thick, and its ore contains about 30% of iron.
56. Geographical Distribution of the British Works.—Most of the British iron works lie in and near the important coal-fields in Scotland between the mouth of the Clyde and the Forth, in Cleveland and Durham, in Cumberland and Lancashire, in south Yorkshire, Derbyshire, and Lincolnshire, in Staffordshire and Northamptonshire, and in south Wales in spite of its lack of ore.
The most important group is that of Cleveland and Durham, which makes about one-third of all the British pig iron. It has the great Cleveland ore bed and the excellent Durham coal near tidewater at Middlesbrough. The most important seat of the manufacture of cutlery and the finer kinds of steel is at Sheffield.
57. The United States have great deposits of ore in many different places. The rich beds near Lake Superior, chiefly red haematite, yielding at present about 55% of iron, are thought to contain between 1½ and 2 billion tons, and the red and brown haematites of the southern states about 10 billion tons. The middle states, New York, New Jersey and Pennsylvania, are known to have many great deposits of rich magnetite, which supplied a very large proportion of the American ores till the discovery of the very cheaply mined ores of Lake Superior. In 1906 these latter formed 80% of the American production, and the southern states supplied about 13% of it, while the rich deposits of the middle states are husbanded in accordance with the law that ore bodies are drawn on in the order of their apparent profitableness.