igneous
Yooperlite
Fluorescent Sodalite-rich Syenite
AI-generated identification · may be incorrectHardness of 5.5 to 6 on the Mohs scale, gray to brownish exterior, and exhibits a bright orange-yellow fluorescence under UV light due to rich sodalite content.
Identified More igneous →
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Physical properties
Hardness of 5.5 to 6 on the Mohs scale, gray to brownish exterior, and exhibits a bright orange-yellow fluorescence under UV light due to rich sodalite content.
Formation & geological history
Formed in alkaline igneous intrusions, specifically glacial erratic syenite boulders originating from the Kola Peninsula and deposited in Michigan's Upper Peninsula.
Uses & applications
Popularly collected by rockhounds for lapidary work, decorative display, and novelty jewelry items.
Geological facts
Discovered recently in 2017 along the shores of Lake Superior, these rocks glow brilliantly when exposed to ultraviolet (UV) light.
Field identification & locations
Easily identified at night using a 365nm UV flashlight, which causes the hidden sodalite to glow intensely against dark beach gravel.
