Why an algae bloom? The free flow of lime green over the periwinkle blue is reminiscent of the movement of smoke, or algae.? The base glass is a periwinkle opalescent glass, and it is capped with a clear/line green streaky glass. Enjoy this stunning handmade glass wind chime in a somewhat protected outdoor area, or inside above a heating vent. Hanging, this wind chime measures 14 7/8” from top the of chain to the bottom of the longest plank.