Yellowing on new outdoor sandstone walkway
Hello, I hope questions of this sort are welcome here, I'm not sure where else to turn. We had this walkway installed last year and within a month of installation some of the pavers turned this yellow-brown color. The issue is isolated to certain stones while neighboring stones are unaffected. The store we purchased the stone from had agreed to replace the affected pavers in spring, but due to life events we did not reconnect and it's now October, so a little late now. It is a quartzitic sandstone, and the research I've attempted to do says it could possibly be addressed with a poultice of rust remover and diatomaceous earth, but I seem to get conflicting answers regarding what products would actually be safe to use on this sandstone. I have not had any luck contacting local stone restoration businesses; I am being told that it is not a fixable problem and haven't even been able to get someone to come out and look at it, although I am unsure if I am adequately explaining the issue, given that it is not a typical weathering discoloration.