Navajo Turquoise

When morning dew covers Kentucky's Poa pratensis meadows, the grass takes on a pale blue-green tint that gave "bluegrass" its name. The hue also lent its name to bluegrass music, where banjo and fiddle carry the freshness of the prairie.

Maya Blue is the most unique pre-Columbian pigment—a mystery that baffled scientists for decades. Maya people heated palygorskite clay with indigo, creating an extraordinarily stable blue that resists acid rain, sunlight, and bio-corrosion for centuries. The secret—revealed in the 2000s with electron microscopes—indigo molecules are trapped in clay's micro-pores, forming a "molecular cage." Maya Blue was used exclusively for rain god Chaac sacrifices. At Chichen Itza's Sacred Cenote, archaeologists found blue-coated human remains—Maya painted victims blue before casting them into the well during droughts.