“The world lacks a great all-around red. Always has. We’ve made do with alternatives that could be toxic or plain gross. The gladiators smeared their faces with mercury-based vermilion. Titian painted with an arsenic-based mineral called realgar. The British army’s red coats were infused with crushed cochineal beetles. For decades, red Lego bricks contained cadmium, a carcinogen.” BusinessWeek on the quest for the next billion dollar color.