Beautiful purple amethysts have been prized since the time of the ancient Greeks. Because of their grape-like color, the Greeks associated these gems with the wine god, Bacchus. They believed that wearing an amethyst could protect you from drunkenness—in fact the word amethystos meant “not drunk” in ancient Greek. According to gemstone lore, amethyst jewelry keeps its wearer clear-headed and clever. Artist Leonardo da Vinci wrote that amethysts enhance intelligence and protect against evil thoughts.