These items are seen here quite a lot and as mentioned before, often as 'porte-perruque' or wig stands.
I've always thought them to be too low for that and in a book that I have got on Belgian glass, they're listed as 'boules de cheminée', decorative ornaments to put on your chimney breast, preferably a pair, but no function or use besides that..
There's one listed for VSL Herbatte division, first half of the 20th C, same drop shape but the stem of the foot is slightly different. I can't comment on the colours as it's a black & white image
