Our poured in place concrete coping was shaped nicely, but 7 wks later, is very inconsistent in color. We wanted the standard grey (chosen from a brochure of Davis colors provided by our PB contractor). There are spots and streaks across all areas of the coping that appear to be yellowish or beige. Our contractor power (not acid) washed the coping 3 wks ago, telling us it would help with the curing but we haven’t seen a change. Is this is a deficiency in how the concrete was mixed or poured? Will it continue curing to a more consistent color?