I spilled a chemical on my Pietra Cardosa countertop, causing it to turn white. How do I restore the color?

Q. I have a Pietra Cardosa countertop, and one handprint sized area has turned almost white on the black counter top because of the spilling of a descaling chemical solution that I was using to clean an appliance. If you have any suggestions for how I would go about getting this back to black or as close to the rest of the countertop as possible that would be greatly appreciated! If there is no DIY solution, based upon information and pictures provided, what would be a cost estimate on getting something like this fixed?
A. Most likely, what you are dealing with is etch damage. The dark surface of the stone has been chemically altered, and that is why it is turning white. Please consult with your stone restoration contractor to remove the etch damage with honing and polishing, due to the extent of damage. Unfortunately there is no easy DIY fix for this problem. The cost for this type of service varies from one market area to another. There are so many variables that will factor into the equation that it would be impossible to answer with any blanket statement how much it will cost. How many diamond grit levels will be required to hone out the damage? How many diamond grit levels will be required to match the honed area to the surrounding finish? A contractor may give you an estimate based on photos alone or want to see it with their own eyes first. Your best bet for the lowest price is to find 2 or 3 reputable contractors and have them bid on the job. This article, Tips for Hiring a Stone Restoration Contractor, may help. Also be aware that SurpHaces PRO Partners are vetted ahead of time.If you do not already have a restoration contractor, contact us. You can request that we check if one of our PROS is in your area. We hope this helps, and we're sorry about your top.