Archaeological excavations of Mound 6 at Ngre Kataa in 2009 expose a workshop where blacksmiths produced iron and copper-alloy tools and ornaments. The mound is being excavated in 2 x 2 meter units named for the coordinates of their northeast corner. In unit 50N 0W (foreground), an area of burned soil marks the location where blacksmiths heated metals. A pottery jar sits in place to the right. In surrounding units (50N 2W, 48N 0W, 48N 2W) are large anvil stones where the hot metals would have been hammered and shaped through forging. The mound's stratified deposits suggest that the workshop area was used for many decades, and perhaps centuries, between the years of about 1350 and 1520 CE (Common Era). View across the mound from the northeast looking towards the southwest. Site Ngre Kataa. 27 June, 2009.
The circular outline of a burned basin (Feature 3) is bracketed by photo scales (center) in unit 50N 4W (130 cm below the unit datum) at Mound 6. A pottery jar sits to the right side of the basin, its opening covered by a potsherd lid. To the left, a grinding stone sits, grinding surface down, over top of another pottery jar. Burned features like these were associated with metal working in this Mound 6 workshop area. Photo scale at bottom in centimeters. Site Ngre Kataa. 29 June, 2009.
The circular outline of a burned basin (Feature 3) is bracketed by photo scales (left of center) in unit 50N 4W (130 cm below the unit datum) at Mound 6. A pottery jar sits to the right side of the basin, its opening covered by a potsherd lid. To the left, a grinding stone sits, grinding surface down, over top of another pottery jar. Another grinding stone (far left) sits at a higher level in unit 50N 6W. A second burned feature is associated with a grinding stone tipped on its side, far right. Another pottery jar sits nearby, also lidded with a broken sherd. Burned features like these were associated with metal working in this Mound 6 workshop area. Photo scale at bottom in centimeters. Site Ngre Kataa. 29 June, 2009.
End view of a fired clay tuyere fragment used in an iron smelting furnace. A thick layer of slag produced during the smelting process coats the tuyere's outside surface (upper right). The tuyere was used to introduce air to the interior chamber of a smelting furnace. The tuyere was collected during site survey by N. Leith Smith in the course of his doctoral dissertation research. The tuyere was recovered in his survey area A, Site 7, Quad P14. Banda area, 8 February, 1997.
Iron slag is formed as a byproduct of iron smelting. Here a large slag nodule has broken in half, revealing its interior texture. At the archaeological site of Ngre Kataa, large chunks of 'bubbly' slag like this were occasionally found in household and other contexts, away from areas otherwise associated with metal-working activities. Potters at the time of the site's occupation had begun to use crushed iron slag as a tempering agent in their potting clays, which may explain why large nodules were being carried and cached in areas away from metal-working locations. Ngre Kataa, June, 2008.
Iron slag is formed as a byproduct of iron smelting. Here a large slag nodule has broken in half, revealing its interior texture. At the archaeological site of Ngre Kataa, large chunks of 'bubbly' slag like this were occasionally found in household and other contexts, away from areas otherwise associated with metal-working activities. Potters at the time of the site's occupation had begun to use crushed iron slag as a tempering agent in their potting clays, which may explain why large nodules were being carried and cached in areas away from metal-working locations. Ngre Kataa, June, 2008.
Side view of a fired clay tuyere fragment used in an iron smelting furnace. A thick layer of slag produced during the smelting process coats the tuyere's outside surface. The tuyere was used to introduce air to the interior chamber of a smelting furnace. The tuyere was collected during site survey by N. Leith Smith in the course of his doctoral dissertation research. The tuyere was recovered in his survey area A, Site 7, Quad P14. A catalog tag indicating provenience information is tied to the tuyere with string. Banda area, 8 February, 1997.