Perhaps not quite exactly on topic, but the multicolored red-yellow-white-blue diamond to the right of the front entrance caught my eye. It can be seen in here:

https://i.imgur.com/naOuD3M.jpg

This picture is not clear enough to make out what it is. I'm very curious what it could be.

(Image source: https://assets.bwbx.io/images/users/iqjWHBFdfxIU/ifII5w8OiDb...)