The Dandelion crayon might be gone ... In 1999, Crayola retired Thistle and replaced it with Indigo. Individually, Thistle is worth about a dollar or two apiece used and around $10 unused.

The ridges of the mortar in between the bricks emit a blue hue, the color of the ocean: indigo, a name that refers to the shrub, the dye the plant produces and the color itself. This crumbling ...