I picked up this clear ashtray (although it doesn't have indentations for ciggies) which is a sort of wavy square shape. It has a geometric design on the base and I assume it's made in a mould.
15.5cm square and 3cm high.
I'm in the US but it doesn't really look like it's from here. I originally though Blenko but all their ashtrays seem to have the indentations to rest your cigarette in.
Many thanks for your continued help.