You're right it has a hollow feel to it, positively a lightweight compared to that lump behind it.
Is it the drawn bubbles to the central pontil on the base that leads you to a possible English player; similar to older English pieces?
It has a very " bright finish " and the basel ring has wear. It's profile has the feel of a larger miniature, slightly rounded at the edges, not a doughnut like the magnum behind it.
It's profile feels like a Clichy piece and the basel ring is similarly proportioned. Is there a typical Clichy profile ratio, I'll happily do a more thorough measure.
Is there a description to the technique used in creating this finish, or could the finish have a name?
I guess you may have asked similar questions.
Would you be able to post pictures too? I know your's will have greater clarity.