Ray

This is the only factory named Vasart (that I know of) and it was called Balmoral. You can speculate on that and knowing the QEII's mother was a collector of Vasart might feed the speculation about who it was made for first - or who bought the first example. It is found signed and unsigned - so made throughout the Vasart periods but until now no examples have confirmed that Strathearn continued to make them.
It is a good piece of design, stable and well suited to the smaller homes of ordinary folk as well as Balmoral Castle.
On your example at 9'o'clock there is a brownish blob, partly obscured by a pale whitish-yellow piece of cane. I have often used this colour as an indicator of Strathearn - in that I never saw it in any labelled Vasart but often in Strathearn pieces. I think Kevin might recently have indicated a Vasart weight with this colour in? Which destroys that theory - if Kevin is right.
We know that Strathearn switched to a new supplier for colours, although Vincent also mixed his own colours from raw chemicals, but if this happened before or after the move from Perth to Crieff is not so certain. It could well be that it falls into that vague transitional period where the same people used the same stocks at both works and there is absolutely no way to differentiate between one or the other buildings production.
Actually, that is not completely true... there is one 'easy' way to distinguish if something was made at Crieff or Perth. At Crieff they used a different type of furnace fired by Propane gas whereas at Perth is was Coal gas fired. The only problem with this easy way is that no one has determined how to test that.
So Kevin, what do you think about my Whitish-yellow theory.
Anyone, do you have a labelled Vasart piece of glassware with that colour in it. Time to broaden the test base.