Optical calcite (also known as “Iceland Spar”) is best known for polarization of light, but some optical calcite will also fluoresce under ultraviolet radiation. This light pink, translucent calcite rhomb seems almost magical until the science behind it is revealed. This calcite is a naturally formed mineral specimen from the location of Nuevo Leon, Mexico. The calcite that comes from this area will turn a vibrant pink under longwave UV (365nm), a golden yellow under midwave UV (307nm), and a ghostly white under shortwave UV (254nm). It even displays the property of phosphorescence after being exposed to shortwave, slowly dimming from white to blue when the light source is turned off. This fluorescent mineral is the perfect specimen for introductory mineral fluorescence study.

• Measures 1.25 inches or more on the longest side
• UV reactive to shortwave(white), midwave(yellow), and longwave(pink)
• Phosphorescent (blue)
• Extracted from Nuevo Leon, Mexico
• Rhombohedral crystal habit