Expanding foam stain on limestone

[NBro]

Does anyone have any idea how to get rid of an expanding foam stain on my lovely fireplace? Have tried gently rubbing with a plastic scourer but that did no good.

Everbuild Foam Eater.

Thanks. Will give it a go.

You need to google 'poultice for marble and limestone' don't use more chemicals please...you could end up etching it or worse. If you've got the worst off, you could just let it weather? It will blend in usually, less risk if causing more damage that way.

In the end I bought a Lakeland magic sponge I'd seen recommended on another thread. It worked brilliantly - just needed some elbow grease! Thanks for the ideas though.