This diamond is an AGS cut grade of 1.  Note the mirrors being pointed at directly at you (black)... those that are positioned towards you (various shades of red) and then those facets that are letting light pass through completely (white).  There are enough mirrors being aimed at us to get decent colored light return and scintillation and there is a presence of strong shades of red around the perimeter of the diamond making for a *good* stone.  Blatant leakage (white) and faint return (pink) under the table causes a hit in white light return.