Description of traditional blast furnace operation in Mazandaran, northern Iran

The blast furnace is situated in an open shingle-roofed shed with a central opening for smoke. Along the long side of the shed are three stalls, one for charcoal and two for ore. The blast furnace, at the centre, is a pyramid of clay about 3 m high. The outer dimensions at half-height are 1.2 × 1.2 m, and the inner dimensions at the mouth are 0.5 × 0.4 m. At the front is the taphole, set back by inset iron bars, and at the side, raised up, is the tuyère.

Connected to the tuyère is a horizontal two-part bellows. The impetus is transmitted directly, with the help of a wooden connecting rod and short iron cranks, by a standing water-wheel, a kind of turbine, as is found in all north Persian mills. On the vertical axle 24 wooden scoops are mounted with carefully fluted blades at an angle of 55°. The removable connecting piece between the bellows and the tuyère is of leather with sheet-iron ends.

In front of the taphole is a sunken forehearth, flat and surrounded by a wall. In front of this is a broad clay floor, and at the side a long wooden trough for the final product.

The iron ore is calcined in the stalls and crushed to nut size. The blast furnace charge per 24 hours is ca. 440 kg ore (weighed before calcining) mixed with 320 kg charcoal. Every 2½ hours – when the furnace is in good working order, 1½ hours – ca. 7.5 kg of iron is tapped, together with the slag, into the forehearth. The iron is dipped out of the forehearth with ladles and, under agitation, spread out on the damp clay floor, so that it is broken up into shot. These small balls are stored in the wooden trough, sorted, and sold as shotgun shot at a price of 5 Schahi = 0.1 Reichsmark per kg. Daily production is 60–90 kg, when the furnace is in good working order, 120 kg, of shot.

It is said that in former times iron for tools and weapons was produced here. This was treated by itinerant smiths in small fineries. Only a few years ago the furnaces of Mazandaran supplied foundry pig to the arsenal in Teheran.

Translated from

Böhne, Erich. 1928. ‘Die Eisenindustrie Masenderans. Stahl und Eisen 48.45: 1577–80.

Last edited by DBW 23 February 2023
Stylistic changes 5 June 2024