Shell

Nacre, also known as Mother of Pearl, is an organic-inorganic composite material produced by some mollusks as an inner shell layer.  It also makes up the outer coating of pearls. It is strong, resilient, and iridescent.

Mother of Pearl attracts prosperity.  Used in mystical work and lore to heighten intuition, psychic sensitivity and imagination.  Protects from negative influence and transmutes negative energy.