I love this trio, the colors and the fluted shape, it's just gorgeous!
Unfortunately it s unmarked so I can't do any reaserch, I can only tell is indeed very old, very fine porcelain.
11th October 2009 -- Update!
I went to a boot sale this morning and I found a plate that looked identical to the ones here, it had a mark on the back....BINGO! that gave me more than a clue about the pottery company: Mayer & Sherratt.
When I came back home I compared the plates, they are not identical but very similar and I have no doubt they belong to the same company. The mark dates from 1906.
This trio seems to be unmarked, but what I think it happened is that the mark was actually worn out.
*About the company:
Mayer & Sherratt
Clifton Works, Longton, Staffordshire potteries
1906 - 1946.