A hidden chamber within a Moche pyramid in the Lambayeque Valley has yielded a cache of 20 perfectly preserved Strombus shell trumpets. Each shell is intricately carved with scenes of mythical sea creatures and masked warriors, suggesting they were the primary instruments for maritime harvest festivals held to ensure the abundance of the sea.
The positioning of the trumpets indicates they were ritually buried as a group after a specific "Festival of the Sea-Spirit" concluded around 500 CE. By analyzing the residue inside the shells, scientists discovered traces of cinnabar and corn beer, confirming that the instruments were used not only for music but also as vessels for sacred libations during the ceremony's peak.