“Amber is the time capsule par excellence: truly forever amber. It formed initially as a resinous blob oozing from a wound or cut on one of several kinds of trees. . . . Insects and other creatures get caught in the ooze. Time darkens it and hardens it. After a few hundred years it becomes copal (often yellow and slick); then after a million or so it acquires the indefinably deep, golden-brown colour of amber. Amber is a resistant material that eventually finds its way into sedimentary rocks. But amber beads still carry within them the trapped insects, sealed until the end of time istself.”

—Richard Fortey, Life: A Natural History of the First Four Billion Years of Life on Earth, 1998.