Patio flagstones need some more color Baird Standish 09 Aug 2013 15:35 EDT

Hi. We have been helping out another contractor remove ferrous oxide deposits on a flagstone patio. He acid cleaned, neutralized and left the patio clean except for yellow deposits. We tested with iron out (and some rs2000 which tested purple). Test are came out clean but the owners would like to color enhance a little. So was wondering what product might provide a mild color enhancement without sealing (want to let stones breath). I believe it was sealed many moons ago, which probably caused the ferrous oxide buildup. Thanks for any ideas.

From the desk of
Baird Standish
Managing Partner
Facility Specialists, LLC
15 West Highland Ave. Suite E
Philadelphia, PA 19118
Phone: 215-732-7505
Fax: 215-546-9160