Those are quite desirable as home decor statement pieces. My father had one that he colourised by pouring yellow varnish into it to coat the inside and then converted it to a floor lamp.
They weren't designed as vases though, but were for transport of liquids in commercial/industrial quantities, or as brewing/fermentation vessels. Over here the rounded ones are most usually referred to as 'carboys', although we also use the term 'demijohn' but more usually for the straight-sided 'jug' forms.
The one my father had was the same rounded shape as yours and had originally been used for the transport of sulphuric acid, in a wooden crate filled with packing straw. It was too big for any of the family to want after my parents died and we sold it (as a lamp, with shade and electrical fitments) for £50 ($64).
PS: Welcome to Tnet.
