I painted mine same as ceiling...I did brilliant white matt emulsion on ceiling, with one Maroon wall and the rest off-Cream.
Painted my plaster cornice (coving if you must !) with a coat of white undercoat paint (which says for wood or metal but what the hell) then 2 top coats of white Eggshell.
Makes it stand out lovely and glossy.
I guess it's important to say my cornice was real plaster, you suggest yours is but I thought I'd better make sure...because the answer could be different otherwise
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