Barbara â€” S&W / RB Alabaster
is difficult as there is at least one other range, probably more, all very similar. I don't even have a definitive list of colours, although orange is known. Documentation is poor, typical of most S&W / RB.
Of one point I am certain. I would be very wary of any identification of Alabaster
from photographs, unless it matched exactly a well-documented piece. Your bowl is similar in shape to Sotheby's 1998 RB Collection sale lot #265, but the proportions are slightly different, possibly a function of size.
Best to take it to a glass fair and/or museum and obtain several opinions.
And please will all those putting up a piece for Id include country of purchase, any known provenance, dimensions, weight, and a photograph of the pontil mark. It may not help, but it could.