I was going to say Callicarpa 'Beauty Berry' as it looks exactly like the one I've got. Either that, or I haven't got what I thought I had and I've got this. Pretty either way.
It's knowing what to do with things that counts - Robert Frost
To also add that the Leycesteria berries are edible but be sure to eat only when they are fully ripe and black, if not then they are very bitter. Taste like caramel.
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Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Pics below of Callicarpa and Leycesteria.
Leycesteria.1-5. Callicarpa. 6-8