Fallout 4 chemistry workstation - background image used for reflections

I've only noticed this today: when the chemical station appeared in the grey-backed loading screen, there appeared to be a transparent image used on the inside of the Florence flask (the big round one at the corner of the worktable).

I managed to capture an example in-game, but it's far easier to see in the loading screen.

Does anybody know what (or where) the image is of? Or how to find the original in the game data?

To me it looks like a 360 degree image taken on the bank of a river, of a town with white buildings and dark red roofs. It does appear to rotate as you move your character around the flask.

The image does not appear to be a reflection of the world around the character, as I took this photo in Diamond City.

So far in my own research, I have found out that the flask type is called a Florence flask (or a boiling flask). Searches on Google images for "fallout 4 chemistry station image in flask" and "fallout 4 chemistry station Florence flask background image" (and others) have not proven very useful.