I think my post was misunderstood and badly written. I wasn't referring to errors in Cyril Manley's book.
I was saying that in Charles Hajdamach's British Glass 1800-1914 where he shows that mark and says it is 'on a slender green alabaster vase with white alabaster foot, late 19th century', I think an error might have been made on his dating:
a) He doesn't actually show the vase in that book. But there is a tall slender alabaster with white alabaster foot vase produced by Stevens and Williams as part of their alabaster range (there are two examples shown in the Manley book and a seller currently has two tall slender vases in other colours for sale in the 'alabaster' range) ... and that range did come in green and white as we know.
b) Hajdamach says in his second book 'self-coloured glass, as it is often known in the factories, was introduced by Stevens and Willliams in the form of their 'alabaster' range as early as 1916 ....'
So I think it is possible that the mark that CH refers to 'might' have appeared on a tall green and white slender 'alabaster' range vase from S&W.
And since the 'alabaster' range was introduced in 1916 that would mean that mark was on a 1916 or later vase ... not a late Victorian one.
Yes, it's possible those little 'vases' might have been 'beakers'. On the other hand, they are very small (narrow at top) for drinking out of, and it is possible that they were supplied to shops in 'batches' so it's possible that a 'batch' or part of a batch of 'vases' , were unsold or sold on when a shop closed I guess.
Interestingly, I often see that mark on the pale blue and white versions of S & W 'alabaster' range pieces (and my pale blue one is marked). And I've seen it marked on two pieces of the cinnamon versions as yours is. I sometimes wonder if it means anything in terms of when the colours were introduced, or perhaps in the method of making, or perhaps in terms of date made.
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