No, you didn’t do anything wrong. When granite is sandblasted the force of the abrasive destroys the crystal structure of the granite. This is why you are seeing a blotchy appearance. Unfortunately the damage has been done and there is very little that can be done to repair the damage.
TIP In a case like this I would recommend flaming the finish. There are available portable flaming devices that will allow you to flame granite in place.
Article ID: 518
Created: January 20, 2022
Last Updated: January 20, 2022
Author: Pam Freitag
Online URL: https://sr-manual.com/kb/article/i-tried-honing-and-polishing-a-granite-tile-that-had-been-sandblasted-when-i-polished-it-had-a-spotting-appearance-did-i-do-something-wrong-518.html