Ray,

sounds like you are working on a dolometic brown maybe one of the emperadors.Try taking the stone up to1800 g diamonds.

If you have good clarity at this point use the mb-12 hot.

Work that first 6-8 sq ft area and get a good polish b4 moving on the next area.You may need to do the first area twice which will help you determine the amount of powder and water you will need to use.Once the pop the finish you will see why mb-12 is so effective.

You should be able to match or surpass factory luster.If you are using the white mb-12 be mindful of the grout lines.

Please call me if you have any questions.