It appears to me,from further reading, that Rose du Barry was a name for one of the colours produced by Stevens and Williams
My reference being: Charles Hajdamach British Glass 1800-1914 page 216 where under the Chapter on Cameo Glass, it is stated
with reference Stevens and Williams Cameo glass -
'...By the early 1880's the pattern books are crammed with cameo designs..... The range of objects consisted of vases, claret jugs.... The number of colours was no less varied and included claret, orange, nut brown, cinnamon, gorse yellow,.......rose du barry, turquoise, amber,....'
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