Mukuba Wa Matwi, Katanga copper 22" long (rear), $650 20.5" long (front), $450 from the Alan Helms collection, Boston, MA ex private NYC collection
"Also called the copper bar with ears and was in the form of a capital "I". Produced by the Sanga. They range up to four feet long. A bar three feet long was the price of a female slave in the 1800's."