Gypsum

Unknown Owner

A classic specimen for this locality with glassy gemmy twinned crystals of gypsum coming off a common matrix. Complete all around with no points of attachment, this is in very good condition. Brightly fluorescent.The Red River Floodway, located on the eastern outskirts of Winnipeg, Manitoba, is a world-renowned locality for "selenite roses," a unique variety of gypsum. Geologically, these crystals form within the heavy, dark grey clays of the Lake Agassiz basin, where calcium-rich and sulfate-rich groundwater precipitates gypsum in the anaerobic, organic-rich sediment. The crystals are typically translucent to amber-colored and form beautiful, bladed clusters or "rosettes" that often contain sand or clay inclusions. Historically, the locality was created during the massive excavation of the 47-mile-long flood control canal, known as "Duff's Ditch," which began in 1962 and was completed in 1968. While the floodway is an active provincial infrastructure project and not a traditional mine, mineral collecting has been a popular activity for locals and visitors for decades, particularly along the banks and secondary excavation sites where the gypsum-bearing clay layers are exposed. Access is generally dependent on water levels and maintenance schedules, but the site remains a classic Canadian locality for high-quality gypsum specimens.