According to 'The Crystal Years'.........the S. & W. use of the name 'Rose du Barry' has nothing to do with 'Alabaster. It was in fact this factory's trade name for their variation of Burmese - which was a name they couldn't use for obvious reasons. S. & W.'s Rose du Barry looks just like much of the regular Burmese even down to the gilding - although whether it 'glows' I don't know (I need a piece

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I'm sure we've been through much of this argument in recent times when I posted a blue piece, which Nigel attributed definitely to S.& W., and that piece has a concave ground/polished pontil mark, and doubtless that is somewhere on the Board's Search facility - it wasn't more than 5 - 7 months back, I'm sure. Looking at the illustration in the book of the S.& W. 'rose' alabaster - it really does look a delicate shade of rose -and not pink like this piece.
As regards enamelled decoration, the book says..............."The output was undecorated except with enamels, and was sold as plain coloured to the Birmingham silversmiths for insets and as vases for flower stands".
Steuben and Richardsons also produced alabaster - Richardsons apparently looking virtually identical to S.&W. (but I don't know if they offered a 'rose'). Carder produced something similar to rose, and called it 'Rosaline', but he seems not to achieved quite S.&W.'s delicate shade of 'rose'.
I'm quoting the above in relation to S.&W. - I have zero knowledge of other Continental offerings, or of the Steuben material - and apologies if it seems like cheating - just quoting from a book.
P.S. Anyway, now we know where Alum Bay got their design idea from for their little milk jug you see quite often

P.P.S - do have a look through the search for the previous discussion - it may offer some more useful information.