New concrete pour black stains?

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We had a new 3500 sq foot concrete driveway poured starting 10 days ago. The first section poured has dark black spots that look like oil stains. Looks horrible, especially now that the driveways is becoming lighter. Any ideas what is this? I haven't tried to wash it because I don't want to impact the curing process. Will these go away as the concrete cures?

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