A couple of the guys have run into this one today… it’s not responding to any level of SH or pressure. Anyone have any clue what it is so i cn explain why it won’t come clean like the brick did?
Is it maybe something to do with the curing process?
Did it get sealed dirty at one point? I’ve seen that believe it or not.
Apparently, someone did that to it on purpose… 
They sealed it dirty on purpose?
Supposedly it was some sort of attempt at coloration that the concrete guy did…
Looks like they sealed over dirty concrete to me. Look at the lighter spot where the mat was.
Yeah, none of it made sense to me… looks like dirty. But the client was happy and said it was supposed to look like that 
