Many thanks Craig
I didn't realise it was quite so old, and at first thought it might be something like Pyrex. The pieces, all 20 assorted, look really fragile because of the thin transparent edges, but have survived well. Its really pretty, and when held to a strong natural light source, has a fiery glow around its thinner edges.
I think this might be a dessert bowl Christine. Its 6" (15cm) diam. x 1¼" (3.5cm) high. There are also some double handled bowls which presumably are soup bowls, flat small plates which I thought might be underplates for either the dessert or soup bowls, larger dinner plates and a beautiful large oval serving bowl with a turned out flat rim, and large oval underplate. When I get time, I'll post some pics. for reference.