Koboibus, mother-of-pearl rings in New Guinea

Even today, large mother-of-pearl rings are still being crafted in some villages in Papua New Guinea in the strictest respect of techniques inherited from ancestors.
In the Koboibus region, the manufacture of these rings is a long-term activity. Its production requires the carrying of heavy bivalve shells during a three-day long inland trek from the islands of Mushu to their destination. Once there, they will be patiently sawn with the braided cord, perforated and polished until they reach the desired shape, conjuring up both feminine forms and the Calao bird.
This "ancestral currency" is intended to be used in ceremonies and processions but can also be used to buy animals and as a dowry. An essential part of the social functioning of villages like Yabomnu or Kuabila, each ring has its own history which also conveys the memory and beliefs of the peoples of New Guinea.