In a library book that has since been returned there was instructions on how to make your own geode. It turned out pretty neat. Some of the crystals are huge. It is an egg shell with salt water (boiled water with salt until it reaches the saturation point). After the water begins to evaporate you are left with large crystals.
We made our Valentine's Day countdown chain complements of Catholic Icing. It is really cute with a bible verse related to love on each link. "Love is patient, love is kind, happy feast of St. Valentine"