Tove Jansson said this quote

Thingumy and Bob sighed contentedly and settled down to contemplate the precious stone. They stared in silent rapture at it.The ruby changed colour all the time. At first it was quite pale, and then suddenly a pink glow would flow over it like sunrise on a snow capped mountain -- and then again crimson flames shot out of its heart and it seemed like a great black tulip with stamens on fire.