Polish coke

The next lesson of history of the metallurgy before the blast furnace coke era is about first European smelting complexes and monks, whose wisdom and cleverness spared the blast furnace technology for the next generations.

The oldest known blast furnaces in the West were built in Swiss village Dürstel, the German region Märkische Sauerland and at Swedish Lapphyttan islands, where the smelting complex was active for two hundred years (1150-1350). At Noraskog in the county of Järnboås (Sweden) there have been also found traces of blast furnaces dated even earlier, possibly around year 1100. Those early blast furnaces, like the Chinese ones, were very inefficient compared to the ones used today. The iron produced in the Lapphyttan complex was generally used to produce balls of wrought iron known as “osmonds”, which were widely traded internationally – as it’s mentioned in a treaty with Novgorod from 1203 and few other English documents from the 1250s and 1320s. Several another furnaces of this period (from the thirteenth to the fifteenth century) have been found in German region of Westphalia.

Historical coke making

Thanks to the General Chapter of the Cistercian monks, knowledge of technological advances was transmitted through the generations. This also includes the blast furnace, as the Cistercians were always widely known as the skilled metallurgists. According to Jean Gimpel, their high level of industrial technology facilitated the diffusion of new techniques. Every Cistercian monastery had an own factory driven by the waterpower, located near the church and being often as large as the church. Such factories had various industrial machines, though they were really universal production and processing facilities. The Cistercians were the leading iron producers in French region of Champagne from the mid-thirteenth to the late seventeenth century and they also produced the phosphate-rich slag from their furnaces, which was used as a good agricultural fertilizer. Archaeologists are still discovering the extent of fine Cistercian technology. Their iron has really great quality, although they didn’t use a blast furnace coke as a fuel.

CATEGORY: blast furnace coke