All the luminous the coloured spectacles which the world in the immensity of space can offer us, nature has produced in miniature amongst precious stones. – Charles Blanc, Art in Ornament and Dress, 1875, translated from French

As though pure white snow flashed and sparkled with the color of bright ruddy wine, and was overcome by this radiance. – Author unknown, about opal

There is in them a softer fire than the ruby, there is the brilliant purple of the amethyst, and the sea green of the emerald – all shining together in incredible union. Some by their splendor rival the colors of the painters, others the flame of burning sulphur or of fire quickened by oil. – Pliny, about the opal

Now the melancholy God protect thee, and the tailor make thy garments of changeable taffeta, for thy mind is opal. – William Shakespeare, The Twelfth Night