Hi,
Just a quick post to confirm(as if any were needed) that the weight is indeed Caithness.As I recall they were known to us as PB 5s(Paperweight Blank).There were several colour combinations depending on what the engraving was going to be.We made a small stock of each and cut them so we could turn round an order quicker.The designs were shown to prospective corporate customers along with abstract and holloware blanks and they would choose what they wanted with their logos or such on them.We haven't made any of these for a long time,the setting was usually done by myself,Rosette Fleming or a girl called Fiona Cumming who worked with us in the 80s.Unusual to see one without engraving on it out in the market.
Allan