It also has a strange appearance on the outside wall, i.e appears paler than the inside colour. This is the same as a couple of lidded boxes I own. Bizarrely it's as though instead of the white of the stems and knops found on some pieces, the white was used to very finely case the coloured opaline on the inside.
There's something about S&W alabaster and no other maker I've found has the same appearance in their opaline glass.
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