How to clean banana leaf sap stains out of wet cast concrete
I work landscape construction. Our crew was removing banana plants near this new built outdoor fireplace, and saved the leaves to make tamales. The laid the leaves on this wet cast concrete hearthstone for a short amount of Timmy and it left a sap stain!
The stain is one day old. The hearthstone is a wet cast concrete architectural slab, meaning that charcoal color of the stain is mixed into the wet concrete as a pigment (I believe that’s a good thing regarding us needing to remove this stain). The slab cannot be removed without destroying a significant amount of the natural stone fireplace we’ve built, so ideally we can clean it rather than rebuild the entire thing.
I see some online articles about banana stains in concrete but the advice is very dubious, and also often refers to the stains from banana fruit juice, not leaf sap.
I know this is a long shot, but does anyone have experience with this? My ideas have been pressure wash, dawn blue dish soap, acetone nail polish remover. I’d love to know whether anyone has advice before trying something that could mess up the concrete finish.