Pigeon blood is a term used to describe a specific shade of red color, often compared to the color of blood from a freshly killed pigeon. This color is highly valued in gemstones, particularly in rubies, and is considered one of the most sought-after shades of red. Pigeon blood rubies, in particular, are known for their rarity and exceptional quality, making them highly prized by collectors and jewelry enthusiasts. The term "pigeon blood" can also be used in art, fashion, and design to describe a similar shade of red.