Moonstone is so well named; the translucent material with the floating schiller looks so ethereal, as if it is lit from within.  It comes in a variety of colours and qualities, (and I have the universally popular rainbow moonstone listed in a separate category) all of which promise some kind of fascinating optical effect.  Moonstone was traditionally thought to be a good luck stone and an arouser of passions and was often offered as a gift between lovers.  Here I have silver grey, white and peach moonstone, all with a strong schiller and pronounced cat's eye.