These are Tillandsias or otherwise known as air plants.
They are alive, oceanic like plants that require no soil.
Tillandsias are very easy to care for.
They need good light and a nice drink about once a week.
Either soak them in water for 20 - 30 minutes (weekly) or spritz them with water every few days.
They are a very unique plant that is incredibly versatile.
Enjoy the exotic plant that transforms into an ocean treasure.