A fine quotation is a diamond on the finger of a witty person, but a pebble in the hands of a fool. – Author Unknown

The hues of the opal, the light of the diamond, are not to be seen if the eye is too near. – Ralph Waldo Emerson

Many individuals have, like uncut diamonds, shining qualities beneath a rough exterior. – Juvenal

How much art and science, and what attention, what care is necessary to render the sun-beams which are imprisoned in a tiny polyhedron of pure carbon, brilliant and sparkling! – Charles Blanc, Art in Ornament and Dress, 1875, translated from French