sorry if I've missed seeing something, but ………………
if it helps at all, I have the following taken from Mark West's 'GLASS Antiques Checklist - small booklet format from the Miller's emporium first published 1994 - page 182 - regarding marks and labels etc.
W.H.B. & J. Richardson -
Wordsley, England. c. 1836- 1850 when it became Henry G. Richardson & Sons (see below).
Signature: enamel decoration and signature. Early decorations were black; later polychrome. One piece of each set was signed:
RICHARDSON'S VITRIFIED
RICHARDSON'S VITRIFIED
ENAMEL COLOURS
Signed on vessel with classical figures painted in iron red:
RICHARDSON'S STOURBRIDGE
Henry G. Richardson & Sons
Wordsley, England. Sold to Thomas Webb about 1930
Trademark, Registration date not known.
follow by: RICHARDSON'S (over a union flag)
with BRITISH (underneath the flag)