I found this yesterday in a shop that does house clearances. I didn't know what it was other than likely a salt cellar. Amazingly, I found what seems an identical one in the collection of Montacute House, Somerset. Please see here:
https://www.nationaltrustcollections.org.uk/object/597427The friezes are crisply cut, but the star on the underside seems purely moulded. The salt measures 5.5 cm high, 7 cm wide, and 4.8 cm deep. It's quite heavy and probably lead crystal.
The Montacute House example is described as "Regency cut glass salt on circular foot." Do you agree with that? Old glass is not my thing, but I just liked the look of it.
Any further information you can give is much appreciated.
Anton