Mariposa calcite, named for the Spanish word for "butterfly," is a variety of calcite characterized by its distinctive two-phase growth and alternating layers of clear calcite and red-brown hematite that create "phantom" or layered patterns.The outer rhombohedral calcite crystals are often yellow to caramel-colored, while the inner scalenohedral crystals, containing manganese, exhibit a striking neon-orange fluorescence under shortwave UV light, making it a prized specimen for collectors.
Locality: Buena Tierra mine, Santa Eulalia, Chihuahua, Mexico
