Don't know if this thread is still open but i have the attached Holborn Pottery inherited from my grandmother who at the time lived in the Glossop area. Some of the pottery shows extensive wear. Gold leaf (or rather paint, more likely) is evident on the less worn tureen but almost completely worn off on the more worn one. I photographed the most legible of the marks but they are all similar - some smudged. This was clearly a mass-market factory. The firing is low-temperature: pottery, not china.
I'm also very curious if anyone has information. These have been used at family dinners for the past 70 years to my knowledge and probably by my grandparents for 20-30 before that. Prior to this I don't have the history, but based on pattern wear and degree of crazing in the glaze it looks like one tureen was added to the set some time after the rest of the set was in use.
Well, if you are looking for the photos, they are not there as i can't figure out how to attach them. They don't exist in the cloud, only on my computer. If anyone can explain the process, I will post, but my large serving platter, 2 large tureens and gravy boat are all the same pattern as the pic already posted.