Mineral - Yooperlite

Name Yooperlite
Class Silicates
Category Syenite with fluorescent sodalite
Crystal system Cubic (for the sodalite contained in the rock)
Chemical composition Igneous rock mainly composed of feldspars, containing fluorescent sodalite (Na₈(Al₆Si₆O₂₄)Cl₂)
Hardness (Mohs scale) 5.5 to 6
Transparency Opaque
Geographical origin Shorelines of Lake Superior (Michigan, USA, and Ontario, Canada)