Miniature Victorian glass cup

Just a little something I found in an op shop...the smallest cup I've seen outside of a toy tea set. And it's made of glass!
The cup measures 4.3 cm tall, 3.5 cm across the square top rim, & 2.5 cm across the polished base.
It is made from clear, pale aqua blue glass, with an applied pale yellow handle - which is finely ribbed, with a "claw" attachment.
There is a crack radiating out from both sides of where the handle is attached, but how could I turn it down?
What would have this been used for? Not tea, not coffee...so maybe for a tiny shot of a powerful alcoholic beverage? I must admit, I have not ever drank out of a square cup, & imagine it could be rather awkward.
It does have the faintest glow under UV light, towards the base of the handle.
Bohemian, English...or whatever!