Engraved, as well as unornamented, ostrich egg shells (OES) were part of the household items of nomadic communities from the Middle and Late Stone age up until the 20th century. Their value initially lay in their nourishing contents but, once empty, the light, strong and durable shell served as a container for that most precious commodity, water. There is an especially high frequency of these shells in archaeological excavations in arid areas such as the Northern Cape and southern Namibia.

Some of the OES found intentionally buried have engraved surfaces. Evidence suggest that they were transported across the landscape as part of a social network linking widely scattered, small groups of people. Jacobson writes that these designs may have been personal markings showing ownership and linked to exchange routes called hxaro. It may even be that designs were added to as the shells continued on their journey from community to community. Geometric designs such as grids, rows of dots, cross hatchings, ladder-like motifs, circles with spokes, triangles as well as images of animals including flying birds and a buffalo have been found.

The geometric decorative designs on the outer surfaces of the shells are most likely symbolically loaded. Abstract graphic renderings of lines, triangles, grids, ladders, zigzags, stars and other markings resemble images engraved onto rock surfaces in the landscape and at sacred sites such as at Driekopseiland, a rocky outcrop in the bed of the Riet River near Kimberly. However, Jacobson and Noli comment that the seemingly abstract motifs could also be images of tangible objects such as headbands, pendants, or nets.

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