John, :hi:
I believe this range is from the period Dobson was in charge - after Michael Harris left, but before Said took over in '75. It's far more sophisticated than post- '75 splodgy stuff - there is a background of acidy yellow splodges, but the orange splodges are part of the "painterly" clear trailing which has been worked over into the main body.
Both yellow and orange are very difficult colours to work. They tend to misbehave.
It is fairly hard to find - most of it turns up in Germany, which was one of the first countries Mdina exported to.
:sm: I tend to describe this as the "intestines" pattern. :sc:
I rather like it and have a small collection. The paperweights are large and hollow.