Copper Celt

A copper celt is an ungrooved chopping or woodworking blade of hammered native copper: a flat or slightly thickened body with a convex or square bit, tapering toward the butt. West (1929) used celt as an umbrella term for copper axes, chisels, adzes, wedges, gouges and socketed spuds, which differ mainly in proportions and hafting.

A nugget was hammered to shape with stone hammers on a stone anvil and ground smooth; heating (annealing) kept the thin edges from cracking. Pounding hardens the edge, but West found no evidence that copper was ever tempered (West 1929; Hodge 1907). West suggested a slotted wooden handle bound with rawhide. Many celts are heavy enough to need a handle, and some axes and wedges have battered butts, perhaps from splitting logs (Milwaukee Public Museum).

Old Copper celts are interpreted as chopping and woodworking tools (Milwaukee Public Museum). In Ohio Hopewell they also carried social meaning: Hopewell Mound 25 alone held 72 copper celts, axes and adzes, the largest weighing over 17 kg (Kocik 2012, after Bernardini and Carr 2005). The key trait is an ungrooved, hammered copper blade with a ground bit and no socket.

Wisconsin (West 1929, converted from inches and pounds): axes 51–356 mm long and 0.23–1.6 kg; chisels 102–381 mm; wedges 76–127 mm; socketed spuds 76–203 mm; adzes in an Oneida County cache up to 464 mm (2.4 kg). Hopewell Mound 25, Ohio: 51–599 mm long, 30–17,270 g (n = 44 of 72); Trempealeau Lakes, Wisconsin: 32–222 mm, 30–1,211 g (n = 11) (Kocik 2012).

Core areas: Wisconsin and the Lake Superior basin (Old Copper) and the Scioto Valley of Ohio (Hopewell). Also Havana Hopewell sites in Illinois and Hopewell-related sites in southwestern Wisconsin (West 1929; Kocik 2012).

Look for an ungrooved copper blade with a ground bit. Socketed spuds have a hollow socket at the butt; adzes are slightly curved, with the bevel on one face only; wedges are short, with a square, battered butt (West 1929). Ground stone celts share the outline but are stone, and copper knives have a long one-sided edge rather than a bit at the end. West (1929) reported that cast copies of copper and brass tools were already circulating among collectors in his day. Bernardini and Carr (2005), cited by Kocik (2012), measured the large Hopewell Mound 25 celt series.