My most recent job of interest involved a Travertine floor. The customer was the victim of a crime spree in her neighborhood. They stole various items and then found a 200 pound safe. They did not expect this treasure trove and did not bring a dolly to move it. So their plan B was to simply carry it out to their truck , which was about 30 feet from the front door. The safe was about 20 feet from the front door. Apparently , the two of them could barely lift it at all. So they decided to just push it across the Travertine floor to the front door. This worked, but left a deep gouge in the floor tiles all the way to the front door. Incidentally, a neighbor saw them struggling with the safe in the front yard, called the police ,and were caught while loading it into their truck. But the damage to the floor was still done.
It had been 10 years since the floor had any maintenance on it whatsoever. So , I started the process by steam cleaning the floor at 220 degees at 2,500 P.S.I. This cleaned all the grout and gave me a good baseline to polish from. Next the fun part. I had to use a 3" grinding diamond wheel at a very coarse cut of 50 grit. The lower the grit the more coarse the stone is removed. I spent about 2 hours just doing a 3" wide cut at 50 grit to get to the bottom of the scratch. Next , I feathered the cut with a 120 grit diamond cutter and widened the area to about 5" . That took another hour alone. Next step , I switched to a 220 grit cutter and widened to about 7 inches feathering the whole cut as I went. This too took about an hour but now you could not even see a remnant of the scratch anywhere.
Now, I switched to a 400 grit cutter and widened my area to about 9 inches feathering as I went.
Finally, after much hard manual effort, I went over the entire area feathering out to about 11 inches with an 800 grit diamond cutter. Because the floor was not super high gloss, I stopped my diamond cutting at that grit. I paste polished the whole area as well as the adjacent kitchen and it all blended nicely and the floor was left level. You could see no trace of the scratch and the floor was shinier and cleaner than ever.
My finishing touch involved coming back the next day to apply a penetrating sealer.Not a fun job to do , but the customer was extremely happy with the end result. Her only other option would have been to replace the tiles. P.S. I also spot ground out some stains caused by urine around her toilet and her kitchen sink. Same process as the scratch removal, just much smaller in scope.