A sapphire is said to bring serenity and purity to the wearer. Wear a pink sapphire pendant for serenity and purity with a splash of fun and irreverence. A perfect stone for nighttime wear, a black onyx pendant looks elegant and stylish in white or yellow gold. Emerald is associated with Venus, the Greek goddess of love and beauty. They say an emerald pendant can protect lovers from unfaithfulness.