In the heart of southern Africa, the ruins of Great Zimbabwe—once the capital of a prosperous kingdom that flourished between 1000 and 1700 AD—still hold the secrets of an advanced iron‑smelting tradition.
Archaeological surveys near the city’s stone walls have uncovered clusters of iron‑smelting furnaces that survive today as mounds of rubble. In the nearby village of Mashava, about 25 miles northwest, fragments of these furnaces bear faint fingermarks, evidence that the ancient craftsmen once smoothed the clay interiors by hand.
Some of the furnaces were nearly as wide as an adult’s arm span, with walls built thick enough to withstand the more than 2,100 °F (1,150 °C) required to melt iron ore. Unlike the bellows‑driven furnaces common elsewhere, these were designed to draw air in and exhaust it through a chimney, eliminating the need for human‑powered bellows.
The self‑sustaining airflow made it easier to maintain the high temperatures needed for smelting, allowing the people of Great Zimbabwe to produce iron tools such as hoes, axes and arrowheads on a larger scale.
These discoveries highlight the ingenuity of the region’s ancient societies and their contribution to the spread of iron technology across Africa.
<small>Source: Ars Technica — read the original story there.</small>
