A regional variant of the earlier Bronze Age 'North Caucasian' culture group, located in the Kuban Valley of southwestern Russia dated to the mid-2nd millennium BC. It was also the name of an industrial complex of the late Bronze Age to early Iron Age, dated to the early 1st millennium BC in the same area. That culture was distinguished by rich Kurgan graves, use of the battle-ax, and a range of metal objects including the 'Pontiac' hammerheaded pin. The heavy concentration of Caucasian bronzes in the amber source zone of east Prussia indicates an extensive amber trade.