Hi paving experts!
I had a limestone patio laid last year and initially there was a lot of efflorescence. This has now subsided however there's now circular marks on the stones which I'm not able to remove and seem to be a reflection of the concrete bed below - I've posted a picture here: https://ibb.co/hqS1KJ. Can anyone please advise on how (or if) they can be removed? It's such as shame as they detract from what would otherwise be a lovely patio!
Thanks very much,
Ed