I have several plain flint examples from Launay Hautin (Baccarat / St. Louis) and they are all around 3.2g/cc. Alas I don't know the colour or uranium profiles, but I understood that the sablee items in that catalogue were no longer made after the early 1840s, which would give them all a quite high density. Nev's reading is suggesting a late 19th century / early 20th century pressing of a pattern first produced around 1840-50. I couldn't rule out Molineaux Webb really, even though it's not in their abbreviated 1870 catalogue. I have items with the same lower half (egg cup) and same upper half (honey) - just not together as a goblet!