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.
Insitu pottery and iron artifacts associated with clusters B and C of what archaeologists interpret as a shrine (clusters A-D) which capped stratified deposits in a metallurgical workshop. Far left in unit 48N 10W, the flat surface of an anvil/grinding stone (GS 09-32) is exposed, to the left (west) of which a poorly preserved portion of an elephant tusk was found (now removed). To the right (east) of the large stone is Cluster B, which includes the group of sherds seen in the vertical exposure in front and left (west) of the tree stump. Behind the tree stump is a large cluster (C) of pottery lids, partial pots and iron objects. Photo scale marked in 5 cm increments. View looking towards northwest. Site Ngre Kataa. 10 June 2009.
Insitu pottery and iron artifacts associated with clusters B-D of what archaeologists interpret as a shrine (clusters A-D) which capped stratified deposits in a metallurgical workshop. Bottom left, at the base of a balk supporting the unit peg, is cluster D, comprised of two stones flanking an iron disc, laid flat (SF 09-158), and a tri-looped iron bangle (SF 09-159). In front and left (east) of the tree stump is a large cluster (C) of pottery lids, partial pots and iron objects, including an iron bangle (SF 09-148) and a pair of miniature iron manacles (SF 09-171, "B"-shaped object). To the right (west) of the tree stump, another cluster of pottery and iron objects can be seen. Top right of the photo, a yellow notebook rests on top of an anvil/grinding stone (GS 09-32), next to which rested a poorly preserved section of an elephant ivory tusk. North arrow photo scale marked in 5 cm increments, arrow pointing north. View looking towards southwest. Site Ngre Kataa. 10 June 2009.
An iron artifact (SF 09-031) recovered from screened soil taken from the southern end of excavation unit 50N 2W where two large boulders used as anvil/grinding stones were located. In the unit's northwest corner was a burned feature interpreted as the remains of a forge in an area where metalworking took place. The flat iron object is pointed on one end and has two rounded lobes at the other, perhaps to facilitate turning (like a key?). Its function is unknown. The object has been corroded by rusting. Scale in cm. Length: 5.7 cm. Weight: 9.3 g. Site Ngre Kataa. 30 May 2009.
View across open excavations in an area (mound 6) that archaeologists interpret as a metallurgical workshop. The photo centers on units 46N 8W (foreground) and the southern half of 48N 8W, the north wall of which (at 47N) can be seen behind the sign board. The exposed areas were excavated in 2008 and the photo taken in preparation for 2009 excavations. Traces of circular burned features, red-orange and yellow in color, can be seen in the freshly scraped surface of these units. The uppermost north arrow sits to the right (east) of the circular outline of a still-buried everted-rim jar. Another everted-jar rim can be seen exposed in the north wall at 47N. This rim and associated artifacts formed cluster B, part of a larger shrine feature (clusters A-D) that extended across the northern half of unit 48N 8W (beneath and behind the small tree trunk visible above and left of the sign board). Cluster A (unit 46N 8W) comprised a large pottery bowl surrounded by six iron bangles that was removed in 2008. It was positioned above and slightly west (left) of the burned feature (center photo) that is intersected by a tree root. Cluster B included the artifacts seen here in the north wall at 47N, together with an associated cluster of a pedestal-handled pot lid, dog skull and jaw bones revealed by further excavation beneath and west (left) of the tree stump. In the upper right of the photo (north and east), insitu anvil (GS 09-15, left) and grinding (GS 09-12, right) stones are visible in unit 50N 6W. Photo scales marked in 5 cm increments and measuring tape marks 2 m. Arrows pointing north. Site Ngre Kataa. 6 June 2009.
Insitu pottery and iron artifacts associated with clusters C and D of what archaeologists interpret as a shrine that capped stratified deposits in a metallurgical workshop. Cluster D appears in the foreground, left, below unexcavated soil remaining around the 48N 8W unit peg. Here two small stones flank a flat iron disc (SF 09-159, left) and a tri-looped iron bangle (SF 09-158, right). Cluster C is a large grouping of pottery and iron objects located north of the tree stump, center photo. Included were several whole pottery lids, a broken but mostly complete jar associated with an iron bangle (SF 09-148) and a pair of miniature iron manacles (SF 09-171). The bangle is visible, resting on a soil pedestal in front of the tree trunk's center. In the photo's upper right, a large anvil stone (GS 09-32), on which sits a yellow notebook, is visible. Flanking this stone on its western edge was a portion of an ivory tusk. Photo scale marked in 5 cm increments. Arrow pointing north. Site Ngre Kataa. 10 June 2009.
Insitu pottery and iron artifacts associated with cluster C of what archaeologists interpret as a shrine (clusters A-D) that capped stratified deposits in a metallurgical workshop. Center photo are two large pieces of an everted-rim jar, its exterior surface facing outward. Immediately above is a large portion of the same pot, its interior surface facing outward. Found positioned against the jar's interior surface was a pair of miniature iron manacles (SF 09-171, "B"-shaped object). An iron bangle (SF 09-148) was positioned at the jar's mouth, above the manacles. To the left of the bangle is the upper edge of a large grinding stone (GS 09-26), which later excavations revealed to be oriented with its grinding surface down. To the right of the bangle, a pedestal-handled pot lid (NK 09-381) rests with its interior surface oriented upward. At center photo, bottom, a pot lid with a strap handle (NK 09-382) rests on its side. To the right of the north arrow, portions of an another pedestal-handled pot lid lie with its interior oriented upward. Photo scale at upper right marked in cm. Arrow pointing north. Site Ngre Kataa. 10 June 2009.
Insitu pottery and iron artifacts associated with cluster C of what archaeologists interpret as a shrine (clusters A-D) that capped stratified deposits in a metallurgical workshop. Lower center of the photo are two large pieces of an everted-rim jar, its exterior surface facing outward. Immediately above is a large portion of the same pot, its interior surface facing outward. Found positioned against the jar's interior surface was a pair of miniature iron manacles (SF 09-171, "B"-shaped object). An iron bangle (SF 09-148) was positioned at the jar's mouth, above the manacles. To the left of the bangle is the upper edge of a large grinding stone (GS 09-26), which later excavations revealed to be oriented with its grinding surface down. To the right of the bangle, a pedestal-handled pot lid (NK 09-381) rests with its interior surface oriented upward. Photo scale marked in cm. View looking south. Site Ngre Kataa. 10 June 2009.
Excavation of a shrine cluster, two images. The image on left shows a pottery cluster, first exposed in June 2008, as it appeared on 10 June 2009. At bottom center of this image is a pedestal base, above which is a tight cluster of rim sherds. The curved sherd on the far right in this image is the outer edge of the pedestal-handled lid, which is fully exposed in the photo on the right, taken on 16 June 2009. A dog skull in a highly friable state is visible above and to the right of this lid in both photos. In the imgae on the right, an iron bangle (SF 09-219) can be seen resting in an angled position, below and left of which is a dog mandible. These were uncovered by excavation below and behind the pedestal base seen in the picture on the left. Photo scale marked in 5 cm increments. Site Ngre Kataa. 10 and 16 June 2009.
An insitu iron bangle (SF 09-132) made from a flattened iron rod with overlapping ends. The bangle occurred as an isolated find in the upper levels of an area (mound 6) that archaeologists interpret as a metallurgical workshop. Photo scales marked in 5 cm increments. Arrow pointing north. Site Ngre Kataa. 6 June 2009.