Possible Clues:

• Mother-of-pearl sources
• Edible mollusks
• Nacre sources
• Rock-clinging mollusks
• Sea-ears
• Moluscs with ear-shaped shells, pearly interiors
• Ornamental shells
• Abo leans out to get shells lined with mother-of-pearl
• Mollusks in oval shells
• Mollusks with iridescent shells