Hi,
I don't remember the weight personally as it was the year before I joined Perthshire but I can maybe give a bit of info on the base.Going by the picture the colour looks like it was a blown cusion base as we called them,which was made the same way as blowing a goblet.First clear glass is gathered on the blowing iron then a white layer, finally in this case what looks like a piece of gold coloured glass (probably Kugler's Goldtopaz) would be "Dropped on" hot by a helper.This would then be worked and blown into a cup shape which when opened out would be filled with clear glass to form a solid base with which to pick up the millefiori design.A total view of the base from the back would better to judge from though

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