The traditional iron industry in Shanxi

A typical landscape in Shanxi, ca. 1930. (George Babcock Cressey, China’s geographic foundations: A survey of the land and its people, New York 1934, p. 185). On Shanxi see also E. T. Nyström, The coal and mineral resources of Shansi province, China, Stockholm 1912.

Shanxi seems fitted out by nature for the iron industry, with the world’s largest deposit of coal, reasonably large reserves of iron ore, refractory clay, and limestone, and not much else in the way of raw materials for industry. And conditions are not good for agriculture, with poor soil and a dry climate. Consequently the iron industry has been, at least in the past few centuries, the dominant economic activity. Coal mining and iron production were sideline occupations for a large part of the peasant population, but it seems that there were also large areas in which iron making was the only occupation. In one town, with a population of perhaps 5,000, people told a foreign visitor in 1898, ‘We eat iron.’

Some experts believe that agricultural conditions in Shanxi have not always been so bad; deforestation has ruined the soil by erosion and ruined the climate by changing the regional precipitation pattern. Other experts disagree. This question can no doubt be answered by research in archives, old diaries, and the like, supplemented by archaeological investigations, but environmental history has not yet progressed very far in China.

The iron and steel products of Shanxi were known for their high quality from very early times. As early as the Tang dynasty the poets Du Fu (712–770) and Lu Lun (737–798) mentioned the famous scissors of Shanxi. For many centuries a large proportion of the needles used in China came from here.

Crucible smelting of iron in Gaoping county, Shanxi, 1898. (Transactions of the American Institute of Mining Engineers, 1904, 34, fig. 1, opposite p. 854).

The earliest description of the distinct ‘crucible smelting’ technology used in Shanxi is that of Ferdinand von Richthofen in 1870. It is quite different from what was used elsewhere in China: a mixture of ore and charcoal is packed in sealed crucibles which are heated, using more coal as the fuel, to around 1200°C for a few days. The iron oxides in the ore are reduced to metallic iron by the coal in the crucible. With this technique there were no great economies of scale, and as Richthofen notes, all of the ironworks were very small.

We do not know how long crucible smelting was practised in Shanxi; virtually nothing is known about it before Richthofen’s description in 1870. Shanxi archaeology seems to show that blast furnaces were used here in ancient times. My guess is that the mountains of the province were forested back then, and that blast furnaces were used as long as the forests could provide charcoal; when the forests at some time were gone, crucible smelting was invented to make possible the use of mineral coal instead. I cannot even begin to guess when this occurred: the Tang dynasty? the Ming?

Shanxi produced in 1870 about 130,000 tons of iron per year. This is an enormous amount, more than we know of from all the rest of China at the time. (It must be remembered that throughout China there undoubtedly was much production for local consumption about which we know nothing.) But the industry was already in decline, as Richthofen observed:

The mining of coal, the manufacturing of iron, and the conveying of both to market employ a large number of men and animals. But notwithstanding its ample resources the country is poor. The profits are reduced to a minimum.  . . . Underground miners, who receive elsewhere 200 to 300 cash a day, must here content themselves with wages of 100 cash. Yet the owners of mines are poor people. There have evidently been better times in this region, as one is justified in concluding from the great number of houses built with luxury, and richly adorned with fine work of sculpture.

The competition with foreign trade is another cause of the decadence of the wealth of [this province]. If we commence with the trifling article of needles, their manufacture in Shansi has almost been annihilated, by the importation of the much better and cheaper foreign article. The same will be true, before long, in regards to guns and steel ware; and there can be no doubt that the injurious effects of foreign competition have been seriously felt by the iron trade of Shansi in general. Being the only noteworthy article of export from that province, the diminished sales and reduced prices contribute to impoverish the inhabitants.

By 1898 the production of iron in Shanxi had fallen to ca. 50,000 tons per year. It increased slightly during World War I, to 70,000 t/yr in 1916, but in 1950 it had fallen to less than 20,000 t/yr.

In 1870 Richthofen gave great praise to the iron produced here, and in fact wrote that it was superior to European iron, but most later witnesses reported that Shanxi iron was quite inferior, containing far too much sulphur. Two samples analysed in 1911 showed 0.13 and 0.61 percent sulphur; even the lower of these values is higher than a smith would want, and it would for example be very difficult to make needles of this iron. In 1958, in connection with the Great Leap Forward, the process was considered unusable, and it was largely abandoned.

It is interesting that the crucible smelting technique was adopted in 1908 in Höganäs, Sweden, where it has the special advantage that it can use poor-quality Swedish coal, which cannot be used in a blast furnace. It seems quite certain that the ‘invention’ of the Höganäs process was directly inspired by the Shanxi process through the Swedish engineer Erik T. Nyström, who taught chemistry and geology at Shanxi Imperial University in Taiyuan for many years from 1902.

Experiments with the Höganäs process showed that the sulphur content of the iron produced could be held down to 0.01–0.03 percent by the addition of a small amount of limestone (CaCO₃) to the crucible charge combined with careful temperature control around 1200°C. It seems to be a reasonable assumption that the iron producers had earlier used limestone in iron smelting, and had stopped using it in order to reduce expenses. Perhaps we see here another example of a technical step backward as a response to competition with cheap foreign iron.

Click on any image to see it enlarged.