Does anyone know what this lens came off of? It has to be ornamental I'd think. Blue is not a color for car lights, airplanes, or boats that I know of. Gary
Since you posted the picture I’ve spent several hours searching and looked at hundreds of lenses and one thing they all have in common is the have a uniform thickness unlike what you have. I’m not sure what it is but I’m pretty confident it’s not a lense.
Could be aviation related. Only taxiway lights use blue lens, runways will be white or clear. End identifying lights will be red and alternating red and white in the last 1000’ or 3000’ feet of runway.