grouting white thassos marble

We recently put down an alternating pattern of white thassos Marble (http://www.lightemprador.com) and (http://maplered.com) "absolute black" Granite (http://tanbrown.org) in our foyer.  While attempting to grout with black grout we had some staining and (http://maplered.com) void fill.  We immediately stopped the grouting process. We have successfully removed the marks from the Marble (http://www.lightemprador.com) with an intensive cleaner.  Before we begin to grout again can you offer any suggestions for filling the voids with a synthetic resin.  A trade name for the product would be most appreciated.

 

Lisa