Blue Glass

I found this fragment of an old bottle.
We see a lot of old glass or ‘pirate glass’ on the beach but it’s always black or a very dark green.
This is the bottom of a bottle with a push up pontil.
The thickness means it’s definitely well over a hundred years old and it looks hand blown. 
Although it has some age, it looks to be recently broken.
I’ve never seen this thickness of old bottle with such a vibrant blue colour. Thought it was worth recording.