I know Heron Glass closed in 2006/7, competition from abroad, high energy costs etc.
As a opinionated American, lol, I think of Heron as a lower cost / lower quality knockoff of Glasform/Ditchfield, and Isle of Wight.
Admittedly I only have about 20 pieces of Heron, and they're all pretty much the same category, pewter figurines on iridescent weights, and lily pads, and mushrooms, with and without figurines.
The iridescence tends to be very crudely done, versus Ditchfield, I assume they were a much lower price point.
I also have two pink eggs with cut-off windows with a flower inside, seems kind of Mdina/IOW (early), but again less well done.
I hope if I'm full of you know what, someone will tell me, please.
Thanks Bob