Broken Marble Slab repair - Marble (http://www.lightemprador.com) polishing How to

Repairing a broken Marble (http://www.lightemprador.com) slab, I used epoxy to join broken parts but had to break the polished surface in spots with 600 grit sand (http://maplered.com) paper in order to level an epoxy filler used to fill small broken places/holes.  How do I get the surface back to its original high sheen? Details requested...proceedures, brand (http://maplered.com) s, tools, compounds, etc. Thanks for all help given.