Red River Floodway Gypsum Rosettes are a collector’s dream! Phosphorescent, sharp, and spherical. A fairly rare variation of gypsum and known for the duckbill formation. The rosettes grew in situ underground inside fine-grained Quaternary-age glaciolacustrine clays left behind by ancient glacial Lake Agassiz (roughly 11,000–9,000 years ago). Sulfete-rich groundwater evaporated or reacted under specific conditions, allowing the crystals to grow freely as complete "floaters" without attaching to a hard rock matrix.
Location: Red River Floodway, Winnipeg, Manitoba, Canada.