Euphorbia marginata is a beautiful plant but, unfortunately, it's not hardy - it might even be an annual. I'm not sure Is there a similar hardy euphorbia?
Euphorbia Glacier Blue's worth considering too. I bought one this morning and chose it after comparing it with E. Silver Edge. Both are very attractive but Silver Edge was more like one I've already got!
The flowers have creamy bracts with a green eye @B3. (Not sure whether that's single cream or clotted cream!) According to a website I've just looked at, E. Glacier Blue is the best variegated form of Euphorbia, we'll see!
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I suppose that depends on how much you've had to drink !!
https://www.gardenia.net/plant/sedum-autumn-charm