The nearest British registered design stylistically that I can think of is Davidson RD 217752 (registered 6 September 1893) which has a pattern of divided diamonds, and comes in opalescent (or more properly, pearline) glass, BUT there are distinct differences in that the divided diamonds are smaller, and come in stacked rows separated by rows of plain diamonds.
(Photo of a Davidon creamer in pearline for comparison).
Also, the Davidson primrose pearline normally has a deeper yellow transparency and is VERY reactive to UV light because of its high uranium content.
The pale citrine colour of your creamer is reminiscent of some of the French and Belgian pieces from the late 19th or early 20th century, but I think most of those pieces are UV-reactive too.
Fred.