OT - Removing Bleaching? Sharpie Marker out of Granite Counter

[rons]

UV will attack the resin in the granite, and is a big known problem if the slabs are stored outside.

I see businesses with storage racks outside all over. Must be that the slabs don't stay in the same position for very long.

 

[akajun]

Maybe try a small steam cleaner ? A real steam cleaner not a hot water vacuum

 

[IceCzar]

No offense, but use of many industrial acids within a home or other confined space should be avoided. The fumes and liquid are harmful to human tissue and can also attack most metals and other materials.

"Mild" acids like dilute citrus or vinegar could be tried, but with testing first.

As they say the dose makes the poison. Hydrochloric acid is a common household cleaner. It's just sold diluted with water and iron impurities making it yellow. Sold as muriatic acid. As a household cleaner it's diluted even more. In the cement and masonry trades you generally cut it considerably less and ventilation/ respiratory protection a good idea.

Mostly used with motars, limestones and marbles (metamorphic limestones) which it will attack/etch the calcite. Granites are a broad spectrum while the quartz component would be resistant the feldspar might not Alkali feldspars would be susceptible. Then there is the resin.

Cheap to test, and probably useful eventually next time you want to prep concrete for painting