are they both marbles or is one granite? If there both marble you should not have a problem but if the black is granite thats a different story. In this case treat the entire floor like it is granite.
One thing to consider if the grout is black. You might want to let them know the the grout lines can lighten when powder polishing. Does not always happen but it can !
--- On Thu, 5/13/10, Stephen Webb <stephen@newlifemarblerestoration.com> wrote:
From: Stephen Webb <stephen@newlifemarblerestoration.com>
Subject: [sccpartners] MIxed stoneDate: Thursday, May 13, 2010, 10:43 PM
Going to polish a small office of a friend that has black and white marble 12X12 checker pattern, any advice would very appreciated. Thank you