The Mbole from the Southeastern D.R. of the Congo made ankle currency bracelets 

which were used for major transactions. 

Some of the largest jewelry forms known in sub-Saharan Africa are found among the Mbole people , Worn by both men and women these large rounded anklets were offered by the husband to his wife to be a part of the marriage contract.

These anklets were forged and hammered from a single ingot.on a custom black iron stands 

15" h by 8" w by 6" L,13.5" h by 8" w by 6"L.

one shows an opening pls check pictures 

thanks