Painting old damaged marble fireplace

[Chas6]

Before everyone shouts 'don't do it!' or accuses me of being a vandal the marble has been painted over at least twice before - the top coat was solid black paint and underneath traces of red paint which has discoloured the original white marble to such an extent that it is completely ruined. So, having stripped all paint off I want to paint it white, preferably gloss. Can someone advise me on primer and paint makes"

Thanks.