Yes you may be right about two layers - I had looked at that possibility. In which case, a lot of work has gone into reducing the layer to a pale green as there are many of the trees and other bits in this paler colour.
Why do I think it's Riedel?
I took a cursory look around when I first bought it, couldn't find anything at all and put it on the shelf thinking possibly contemporary and forgot about it

This afternoon moving 'stuff' around I decided to photograph it and took a much closer look. There are seeds (quite large ones) and pits and black specs in it. In the hand it doesn't look like new glass - can't explain any more than that really. The background is not sandblasted to achieve that effect but has been acid etched - in parts in the light you can see where the satin background (clear glass) isn't 'even' on the surface - hard to explain but I have a piece of sandblasted cameo and it's not the same ( I realise that doesn't make it 'old' but just a pointer I suppose). And I just suddenly felt that it wasn't a new piece. Can't explain exactly why other than those two things.
The lighting makes it look very ethereal, it's very hard to photograph it to make it look 'substantial' , but also show the different colour effects and layers, because of the colours and the transparency.
I do have two pieces of French cameo that are much thicker and heavier. It's not the same 'substantial' as those - a very different animal, I think that's what makes it look contemporary. But I just don't think it's new

I found some Kralik cameo in the Passau that has a similar look and design idea that I'd remembered from searching for something else, which led me to looking for period pieces and finding some Riedel cameo pieces, in a different vein but which had enough similarities to make me look further, which led onto this thread here :
http://www.glassmessages.com/index.php/topic,38278.msg210942.html#msg210942I've added some pics - the best I can do lit from the front - the shape of it and where the cameo is, makes it difficult to show both top and bottom evenly lit. It doesn't show the mix of satin and gloss glass finish in the individual bits unfortunately.
The second pic is another frit or stones which should also show black specs in the glass around it hopefully.
The last is an example of the background bumpiness, difficult to show when lit to photograph but this is the part I could get to show in the lighting.
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