If, as we expect, this weight is from the Harland period, what colour should I see under the shortwave UK lamp?
Prepare to get confused ... Depends upon which of my articles (or which book by other authors) I use for reference!!
In my web article linked to earlier, I said "Dusty Light Green". I also said the same for pre-Caithness period Ysart items. But later I preferred "Dusty Grey", which returned to a general agreement with the detail in Bob Hall's book Scottish Paperweights
. That was back in 1999/2000 and the few years following.
In 2009, Colin Mahoney (probably America's foremost authority on Ysart weights) wrote a book, Masterworks: The Paperweights of Paul Ysart
. In his book, he gave a table of UV results for each period of Ysart items. For Harland/Highland he stated "None" for the shortwave UV reaction. He also stated "Cloudy yellow-brown" for the shortwave reaction of pre-Caithness Paul Ysart pieces.
Maybe the quality of darkness used for UV tests in California differs from that in England :huh:, but I still think "Dusty Grey" is closer to what I see.
However, the important point is that the shorwtwave reaction of a Harland period weight will not
be Blue, whereas for a Caithness one it will
be Blue. Before the Caithness period, as far as I know, Paul Ysart did not make Flower-on-Latticino-Cushion weights with the extensive use of bright aventurine (or mica?) as seen in your weight.