The opá iku is used when praying the moyuba (mojuba) on the ancestors, by tapping it on the bottom to contact up Egun to get existing. Within the Yoruba homeland, the tapping of this personnel was basically carried out along with the graves on the buried ancestors in the house https://natasha-howie31963.blogdon.net/not-known-details-about-la-rdc-aux-pays-suivants-44942477