Thank you Pamela for making me look at this item more closely.
I think I may have made a mistake, apologies.
The mould line is on the ruby parts only. No sign of a mould line on the cut parts or on the inside of the ashtray.
So can we presume the ruby parts are moulded and the clear glass is hand blown? I'm not really sure about the process involved when flashing glass, it is all beyond me at the moment.
Or does the mould line on the ruby parts indicate blow moulding?