Shells from rivers or the sea, such as these from Los Millares, were probably used while tied together with a hemp or esparto grass cord, which no longer exists. By tying them together, it was easier to strike them against each other to produce sounds. In other examples, they hung from belts, wristbands or ankle bands in order to produce sounds as the wearer danced. This function was in addition to their purely esthetic appeal, given the beauty of the prized mother-of-pearl they contained.
The snail shells suggest more complex use, since they contain holes drilled in a premeditated fashion. Ethno-archeo-musicology has attempted to determine the type of sound they produced and how they were played. These snail shells could be played much like a horn. The user would blow into the narrow opening in order to make use of the rest of the snail shell as a resonating chamber, thus amplifying the sound. By partially covering certain openings, the sound would vary. This was one of the first truly musical manifestations in human history.