I have acquired two sets of porcelain. One is definitely Britannia with the capital letter B and two C’s within it, but the other set has no marks, but is very similar. Edge is the same, handles on teacups the same and both have an acanthus shape, but the unmarked is demitasse and has two birds on it. Both are Cobalt and gold. Was all Britannia marked and is it likely that they are both Britannia?
The first photo is the one in question, the second photo has the Britannia mark.