Red River Floodway, Winnipeg, Manitoba, Canada
Click on photos for a larger image.
All the Red River Floodway gypsums fluoresce and phosphoresce. They grow in the clays beside the Red River and so are free-floating (although--especially in the upper layers---they may be joined together). All grow from central nuclei (sand or organic material) but the final shape varies with depth. In the upper levels there are flattened plates ("sunbursts"). At deeper levels, there are spectacular “sputniks,” with large, twinned blades. The deepest layers produce clear, spherical clusters with chunky crystals and fewer twins.