These are one of a kind magic Pebbles that change color at night when they are turned on. Each one has been hand painted with transparent natural inks, carved & engraved. The pebbles shaped ones measure 12 by 5.5 cm & the round ones 7by 7cm. in the photos below; the first three shots are in daylight & the last at night. They create a very calming presence in the home. They are great for relaxing , meditation & yoga. Cosmic Lights, Meditation Stones, Yoga Lamp, Magic Pebbles That Change Color