This is a style of script I associate with '70s and '80s. It appears in this style in both a thick "dremmelled" sort of appearance (often on pink splodgy stuff as in trailed decanters with coloured prunt, produced in the '80s, but also in a diamond point etch.
(The slimmer line I asociate with '70s, the thick with the '80s.)
I did, once, many years ago, attempt to go through all the differing scripts, but gave up after identifying about 25 variations.
I suspect there are many different hands, all attempting to produce something similar - as would fit in with what we know about it being simply a matter of stuff getting marked only if and when there were staff, time and equipment to do so.