without going into the technicalities of the whole process, satin air-trap - regardless as to whatever final form it took - seems always to have started life in a dip mould. So I suppose mould marks could be found - but as far as I know the moulds were not the usual 'pressed glass two part hinged type moulds', where seams etc. are more or less the norm. I've only ever had one piece of this stuff so probably shouldn't comment - but mine was good quality - but presumably lesser pieces might have been made differently.
This stuff became big business in Europe in the C19, some of it mind-blowingly complex and to die for, but like anything that looks to be a money spinner, people jump on the bandwagon and quality drops.
If you have Hajdamach 'British Glass 1800 - 1914', I think there are some pix there.