Hi Lenore.
This will have been made by caithness as i am almost sure they bought the paper weight arm from whitefriars before they closed or as they closed, i will have to read though my MOL book, and find out, but the date is 1986, take a look at this, seems to be a cut one with the same pattern,
http://tinyurl.com/56gc3t you could always take a look here too, might help,
http://www.whitefriars.com/ under the paper weight section
If i find any thing in the MOL book i will report back.
good luck Sg